Five postings in 2011 on books and subjects related to the mind and brain, and I was consciously aware of that fact and a desire to move on to something new. But as I wrapped up V.S. Ramachandran's The Tell-Tale Brain (see previous post), his remark that as neuroscientists map the brain they are "grouping their way toward the periodic table of elements" reminded me that a book on The Bookshelf that I had purchased last year, Rita Carter's Mapping the Mind, was waiting to be read. I found this book at the bookshop at the conclusion of the American Museum of Natural History's exhibit on The Brain. I recalled that what impressed me toward a purchase was the exquisite drawings of the brain, many of which included arrows to illustrate the interconnectedness of specific brain regions to explain a specific neuronal process. For those who are not practicing neurologists, a picture can nicely supplement a thousand words.
By the end of Mapping the Brain, I wondered if this should have been the first book I ever read on the brain. Would I have better appreciated all the other material I have read on this subject if I had already read this book? I can't answer that, but studying Rita Carter's text after I had read these other books, many of which are discussed or mentioned in prior posts, was facilitated by my prior exposure to the subject. Either way, Mapping the Brain is a good overview and introduction to the brain and a good review as well.
Ramachandran's analogy that neuroscience's understanding of the brain is moving in the direction of establishing something akin to chemistry's periodic of table of elements is best left as a metaphor rather than a suggestion of equivalence (as I think the statement was intended). It is fair to say, like the periodic of table of elements, that the brain is organized, but it is not sequential in the same sense that the elements can be organized sequentially according to their atomic weight or related in their properties as part of one of 18 different groups. While thinking about this, it crossed my mind that evolutionary age would be one way of sequentially organizing the parts of the brain. Antonio Damasio did something like this in Self Comes to Mind (see April 8, 2011 post), describing the sequential evolution of the brain stem, the limbic system, and ultimately the cerebral cortex. But the brain is indeed very complex, as Carter notes in her closing paragraph, when she says that "today's mind voyagers are discovering a biological system of awe-inspiring complexity." One could also try to organize the parts of the brain sequentially, starting with a particular sensory input, and follow the connections to other parts of the brain to conscious awareness and action (or unconscious action, as the case may be) that ensues. In the end, however, that effort would not be particularly useful given the multi-layer network of sensory inputs that are processed simultaneously, including the presence of variable emotional reactions in connection with a particular sensory input that could stimulate a different behavioral outcome.
Both Carter and Ramachandran caused me to question a statement I made in a prior post (June 12, 2011 post) while discussing Michael Shermer's The Believing Brain. I wrote:
"I strongly suspect that if we dissected human brains and a network of connected neurons from a representative sample of humans, we would find a very high level of near identity among brains. There will be some differences due to DNA, and there will be some pathological differences as well, perhaps caused during embryonic development. But I believe that by and large we will find that human brains, neuron by neuron, are organized and folded and layered in substantially identical ways." There is substantial truth in my remark --- I did not say identical, but I did say "near identity" and "substantially identical." These words came at the risk of maybe overstating the case. Carter writes, "Human brains are constructed along fairly standard lines and so we all tend to see the world in a fairly standard way." And as I noted, there are differences due to DNA, pathological injury, and embryonic development. But I overlooked perhaps the largest exception --- experience (nurture) and its impact on memory -- and what is referred to as synaptic plasticity. And it is long-term memory -- enhanced by repeated experiences in some that others do not share --- that gives rise to our autobiographical self and what makes each one of us unique. So while we may "tend to see the world in a fairly standard way," Carter notes:
"Every brain constructs the world in a slightly different way from any other because every brain is different. The sight of an external object will vary from person to person because no two people have precisely the same number of motion cells, magenta-sensitive cells, or straight line cells. . . . An individual's view is formed both by their genes and by how their brain has been moulded by experience. Musicians, for instance, have brains which are physically different from others and which work differently when they play or hear music. . . . Extraordinary individual ways of seeing things may also arise from strange 'quirks' of brain development. Albert Einstein, for instance, had a very oddly constructed brain which might account for his astonishing insights into the nature of space and time."
Carter's treatment of language pretty much follows that of Ramachandran. And her treatment of memory restates much of what Antonio Damasio (see April 8, 2011 post) and Daniel Schacter (see September 20, 2011 post) discuss, but I still learned something new. For example, "Episodes that are destined for long-term memory are not lodged there right away. The process of laying them down permanently takes up to two years. Until then they are still fragile and may quite easily be wiped out. It is this replay from hippocampus to cortex and back again -- a process known as consolidation, that slowly turns fleeting impressions into long-term memories. . . Much of the hippocampal replay is thought to happen during sleep. Recordings from hippocampal cells show them engaging in a 'dialogue' with cortical cells, during which they signal one another, back and forth, in a call-and-reply formation. Some of this is known to take place during the 'quiet' phase of sleep, when dreaming, if it occurs at all, and is vague and instantly forgotten. Until memories are fully encoded in the cortex they are still fragile and may quite easily be wiped out. And even when they are established, they are not fixed. A memory is not, in fact, a recollection of an experience but the recollection of the last time you recalled the experience. Hence our memories are constantly changing and redeveloping. The process by which a memory changes is more or less the same as the consolidation process that lays it down for the first time. As we will see, each time we recall something, it is changed a little because it becomes mixed up with things that are happening in the present. Reconsolidation is a process by which this slightly altered memory effectively replaces the previous one, writing over it, so to speak, rather like re-recording over a rewritable DVD." I mentioned this phenomenon in the September 20, 2011 post discussing Daniel Schacter's discussion of the consistency bias, whereby the brain infers past beliefs from our current state and the reference to Joseph LeDoux's discussion of reconsolidation. Carter explains it better.
I also learned that not all memories are stored in cortical areas. While long-term memories are initially stored in the hippocampus, as described above, over the course of roughly two years they are transferred to the cortex and the hippocampus is no longer required for their retrieval. These memories are distributed in the same parts of the brain that encoded the original experience. So sounds are found in the auditory cortex, taste and skin sensory memories are found in the somatosensory cortex, and sight in the visual cortex. But procedural -- "how to" --- memories are stored outside of the cortex, in the cerebellum and putamen, and fear memories are stored in the amygdala.
Carter also addresses, albeit briefly, the subject of imagination, which I have touched on in several previous postings (see, for instance, July 30, 2011 post and May 22, 2011 post) and describes the connection to memory. "Our ability to conjure up scenarios which have not actually happened is prodigious. Imaginative capacity runs along a spectrum from the mundane skills required to envisage what your supper might taste like if you combined the onion, mushrooms, and left over chicken in the fridge with some curry sauce, through to the awe-inspiring visions of artists, writers, and excitable children. Even the humblest of these skills outranks the abilities --- as far as we can tell --- of every other species. . . . At first sight memory and imagination seem quite distinct: the first in concerned, after all, with what happened already whereas the second is all about what has not. But recent studies show that imagination is wholly dependent on memory, because memories are its building blocks. When we imagine something happening we root around in our memory and come up with experiences which seem likely to recur, then combine them, chop them, shake them and blend them until they come out as something entirely different." In my view, this is cannot be unrelated to the process of reconsolidation that I mentioned above and some of the biases that other writers have described (see September 20, 2011 post and June 12, 2011 post) whereby memories are altered.
A text box entitled "Remembering the Future" by Eleanor Maguire is inserted by Carter, which perceptively quotes Lewis Carroll's Alice in Wonderland: "It's a poor memory that only works backwards." Maguire cites an MRI study that found recalling past experiences and imagining future possible ones activated a network of brain regions in common including the hippocampus. She notes a new theory of 'scene reconstruction,' which allows for the internal rehearsal of events or scenes, which underpins the process of creating a simulated event. Maguire writes: "[I]n humans, the use of this scene reconstruction process goes far beyond simply predicting the future, to general evaluation of fitness for purpose and ultimately creativity. For example, a scriptwriter or novelist who is writing a passage in a film or book may play out the whole scene using their construction system, not with the idea of predicting the future, but instead for the purpose of evaluating its aesthetic suitability." This is the sort of discussion I was hoping to find in The Tell-Tale Brain (see previous post). What is missing from her discussion is the identification of the parts of the brain involved in imagination, although the text seems to identify the hippocampus as one candidate for assembling disparate memories. Also missing is the evolutionary basis for this ability. Obviously, the ability to plan for the future has survival value, and our planning capacity is lodged in the frontal cortex, where working memory occurs. The building blocks for understanding creative imagination are before us, and understanding a collateral capacity --- the capacity for deception, including self-deception --- by imaginatively rearranging memories and treating them as factual, when they are not, needs to be understood as well. Part of this is reflected in the previous discussions of mental biases. Carter notes that the subject of belief and non-belief is not unrelated to how the brain treats statements it believes to be true and those it believes to be false. Research, she says, shows that truth telling appears to be the default position for the human brain, and that telling lies involves extra cognitive effort. I am not sure this is entirely true, as bias mechanisms appear to be short-cuts for resolving conflicts in our memories.
Sunday, November 6, 2011
Tuesday, October 25, 2011
V.S. Ramachandran, The Tell-Tale Brain (2011)
My original expectations for this book never materialized, but still there was much learned . From my cursory examination in the bookstore, I was expecting to learn something about the role of the brain in creating art, particularly storytelling, works of fiction and imagination. I noticed a couple of chapters on art and aesthetics, but these turned out to be ruminations and speculation on the role of the brain in appreciating visual arts. That is not to say these ruminations were without value, but only that I was expecting a different treatment of the subject.
Second, I knew that V.S. Ramachandran , one of the world's leading neuroscientists, promoted research findings about mirror neurons, a subject that was covered in the September 18, 2009 post discussing Marco Iacoboni's book, Mirroring People. Ramachandran, however, despite his disclaimer that mirror neurons do not explain everything about the brain, seems to suggest that they explain an awful lot: certainly a lot more than the subtitle of Iacoboni's book suggests --- empathy for others and how we are able to comprehend the actions and perhaps the intentions of others from their body movements. Ramachandran suggests that mirror neurons may also be key to understanding our own self-awareness: awareness of what our own mind is thinking. Regrettably, the proof is not yet there to support his surmises in this regard; too often Ramachandran says that this area of the brain is involved in such and such, and that area of the brain is known to be rich in mirror neurons, and with that association it might be the case that mirror neurons explain such and such. That is not to say he is wrong, but he may be more right than wrong when he says that mirror neurons do not explain everything.
Here is an example of what I just said. Ramachandran strongly believes that mirror neurons, while initially identified in monkeys, are an important piece in understanding human evolution. "[O]nly in humans do they seem to have developed to the point of being able to model aspects of others' minds rather than merely their actions. Inevitably this would have required the development of additional connections to allow a more sophisticated deployment of such circuits in complex social situations. . . It is difficult to overstate the importance of understanding mirror neurons and their function. They may well be central to social learning, imitation, and the cultural transmission of skills and attitudes --- perhaps even of the pressed-together sound clusters we call 'words.' By hyperdeveloping the mirror-neuron system, evolution in effect turned culture into the new genome. Armed with culture, humans could adapt to hostile new environments and figure out how to exploit formerly inaccessible or poisonous food sources in just one or two generations --- instead of the hundreds or thousands of generations such adaptations would have taken to accomplish through genetic evolution." This is an astonishing hypothesis, to borrow a phrase from Francis Crick. But Ramachandran strongly believes he is on to something because of the presence of mirror neurons located in certain parts of the human brain that are relatively unique to humans, in contrast to the apes, our nearest relative. Ramachandran is referring to Wernicke's area in the left temporal lobe (the area of the brain that is responsible for our comprehension of language -- where speech acquires meaning), the prefrontal cortex (an area responsible for decision-making and cognition, which includes the motor cortex where commands are sent to muscles for movement, and it includes Broca's area, which is responsible for speech), and the inferior parietal lobe (IPL). In humans, Ramachandran notes, the IPL evolved into two parts not found in apes --- the supramarginal gyrus (an area responsible for our ability to "visualize" words and action) and the angular gyrus (an area of the brain that Ramachandran says is connected to metaphor comprehension, but also finding a common denominator between two superficially dissimilar things). The genetic change that created these areas of the brain "rich in mirror neurons," surmises Ramachandran, "freed us from genetics by enhancing our ability to learn from one another" --- "liberat[ing] our brain from its Darwinian shackles, allowing the rapid spread of unique inventions" (tools, new words, constructing shelter, creating communities) that are at the foundation of culture. "Instead, increased sophistication of a single mechanism --- such as imitation and intention reading --- could explain the huge behavior gap between us and apes."
Ramachandran is a neuroscientist who has a wealth of clinical research observations about damage to specific areas of the brain and the consequences of that damage. And with that wealth, my appreciation for the role of specific areas of the brain and their connections to other areas of the brain during normal operations continued to grow. Other books, some of which are discussed in previous posts, have contributed to my appreciation, but Ramachandran's presentation in this book, including his drawings of the regions of the brain together with his glossary and specific case studies begins to put it all together. From a big picture point of view, with this book Ramachandran is pursuing the same subjects that Michael Gazzaniga pursued in examining what makes us "human" (see September 27, 2009 post) and that Antonio Damasio pursued in examining what creates our sense of self (see April 8, 2011 post). And Ramachandran contributes his own views on the origin of human language, a subject that was extensively reviewed in Christine Kenneally's The First Word (see August 31, 2009 post).
Let's discuss Ramanchandran on the evolution of language, because this is really the part of The Tell-Tale Brain that demonstrates what I have just said about this book. In discussing the evolution of language, Christine Kenneally reviews the views of Noam Chomsky (language is not the outcome of evolution, but is simply a built-in property of the brain), Stephen J. Gould (language initially evolved as a way to represent the world --- namely thinking about the world, and only later became a means of communication), and Steven Pinker (language is an instinct, an adaptation that is unique to humans that evolved specifically for communications purposes). Ramachandran does likewise, dismisses Chomsky quickly (his thesis cannot be tested), and then says that there is a grain of truth to both Gould and Pinker, but they just did not go far enough. For Ramanchandran, language did not evolve from some general mechanism for thinking, but neither did it evolve specifically for purposes of communication. What is innate and what evolved, says Ramachandran, is the competence to acquire rules of language. The actual acquisition of language occurs as a result of social interaction. Ramachandran believes that language was enabled by cross linkages in the brain between different motor maps (e.g. the area responsible for manual gestures and the area responsible for orafacial movements). Ramachandran calls this synkinesia ("together" "movement"), but he is borrowing from research on synesthesia, a brain phenomenon where senses are joined by cross-activation of two sensory maps. Thus what humans have is a built-in capacity to for translating gestures (movement) into words. The original "words," if you will, may have been grunts or other noises that accompanied a gesture (a proto-language). Synkinesia alone probably does not explain speech and language, but the human capacity for mimicry is critical as well, and hence the subject of mirror neurons enters the discussion of speech development, and again we return to the linkages between Broca's area, Wernicke's area, and the supramarginal gyrus and the angular gyrus in the IPL that enable what Ramachandran labels "cross-modal abstraction."
Ramachandran borrows from Gould the latter's concept of exaptation. An adaptation is an evolutionary response to natural selection. An exaptation is a refinement of an adaptation whereby a function is borrowed and used for a different function. Ramachandran believes that the IPL did not evolve for higher forms of abstraction such as giving names (words) to something, but evolved to provide hominids for refined interaction between vision and muscle and joint position while negotiating branches on tree top, a type of cross-modal abstraction. A subsequent exaptation was the development of these areas of the brain --- and their capacity for abstraction --- to develop tools and subassemblies of tools (e.g. an axehead and a suitably designed handle), says Ramachandran. He sees "a tantalizing resemblance" between the wielding of a tool made from composite parts and a full blown sentence including noun phrases and verbs. Speech, including syntax, emerged from the area of the brain that was key to tool manufacture, he speculates, and this became Broca's area. Add to that the areas of the parietal lobe (Wernicke's area and the IPL) and the human brain now has a language acquisition device. By the end of his discourse, Ramachandran concedes that he has been speculating on the evolution of language and thought, and he still has not resolved it, but he believes that it is not inconsistent with what neurologists know about patients who are damaged in these areas of the brain, and what we know about the evolution of other body parts. The problem is that language and abstraction are "software," and they can't be found in the fossil record that is all we have to understand what happened tens and hundreds of thousands of years ago. Unlike Christine Kenneally, Ramachandran does not discuss the debate over the FOXP2 gene and its possible connection to human language. Ramachandran asks, why were genes for language competence selected, but he does not illuminate what those genes might be., and perhaps that is because he recognizes that language is the outcome a several different modules in the brain, and there can be no single gene that would explain that fact.
There is much more to this book than just mirror neurons and the evolution of language, but there are discussions of memory, brain plasticity, the self, and free-will. Marco Iacoboni believes that, in view of research on mirror neurons and social behavior, the concepts of the self and free-will are blurred --- at least our Western sense of the individual is not as real as we sometimes think. (See September 18, 2009 post). Just how "free" and unique are we? he asks: Self and other are inextricably blended, says Iacoboni, and our behavior is subtly influenced by mirror neurons which produce automatic imitative influences based on what others are doing or saying. Iacoboni believes we have only "limited autonomy." Ramachandran does not touch this subject, but he does profess that humans have a sense of agency --- a desire to act and our belief in our ability to perform that act. Ramachandran says that there is evidence that the anterior cingulate in the frontal lobe is involved with wanting and intention. Damage to this area leads to apathy. The anterior cingulate, says Ramachandran, receives inputs from the parietal lobe, including the supramarginal gyrus, which as noted above, is involved with our ability to conjure up images of action (movement). These connections lead Ramachandran to believe there may be a neurological basis for free-will, signifying that it is not just a philosophical problem.
Ramachandran summarizes the current state of neuroscience with a comparison to chemistry: neuroscience is now at about the same stage that chemistry was in the 19th century, discovering the basic elements, grouping them into categories, and studying their interactions. As neuroscientists "map" the brain, they are "grouping their way toward the periodic table" of elements, but are not anywhere near atomic theory. As I noted in a previous post (see January 21, 2011 post and April 8, 2011 post), this is not fatal to the proposition that the era of skepticism is over. Ramachandran notes numerous experiments that remain to be started that would confirm one hypothesis or another.
And a final note. While Ramachandran failed to provide specific insight into how the brain creates art or fiction, on reflection, the elements of that mechanism may very well have been covered. We are, after all, talking about imagination, and the parts of the brain that enable abstraction, when combined with the parts of the brain that enable language (not just speech, but semantic content as well), when combined with the parts of the brain that enable us assemble things and to mimic what others do, must be involved in the creation of fiction and other forms of art that are the production of imagination.
Second, I knew that V.S. Ramachandran , one of the world's leading neuroscientists, promoted research findings about mirror neurons, a subject that was covered in the September 18, 2009 post discussing Marco Iacoboni's book, Mirroring People. Ramachandran, however, despite his disclaimer that mirror neurons do not explain everything about the brain, seems to suggest that they explain an awful lot: certainly a lot more than the subtitle of Iacoboni's book suggests --- empathy for others and how we are able to comprehend the actions and perhaps the intentions of others from their body movements. Ramachandran suggests that mirror neurons may also be key to understanding our own self-awareness: awareness of what our own mind is thinking. Regrettably, the proof is not yet there to support his surmises in this regard; too often Ramachandran says that this area of the brain is involved in such and such, and that area of the brain is known to be rich in mirror neurons, and with that association it might be the case that mirror neurons explain such and such. That is not to say he is wrong, but he may be more right than wrong when he says that mirror neurons do not explain everything.
Here is an example of what I just said. Ramachandran strongly believes that mirror neurons, while initially identified in monkeys, are an important piece in understanding human evolution. "[O]nly in humans do they seem to have developed to the point of being able to model aspects of others' minds rather than merely their actions. Inevitably this would have required the development of additional connections to allow a more sophisticated deployment of such circuits in complex social situations. . . It is difficult to overstate the importance of understanding mirror neurons and their function. They may well be central to social learning, imitation, and the cultural transmission of skills and attitudes --- perhaps even of the pressed-together sound clusters we call 'words.' By hyperdeveloping the mirror-neuron system, evolution in effect turned culture into the new genome. Armed with culture, humans could adapt to hostile new environments and figure out how to exploit formerly inaccessible or poisonous food sources in just one or two generations --- instead of the hundreds or thousands of generations such adaptations would have taken to accomplish through genetic evolution." This is an astonishing hypothesis, to borrow a phrase from Francis Crick. But Ramachandran strongly believes he is on to something because of the presence of mirror neurons located in certain parts of the human brain that are relatively unique to humans, in contrast to the apes, our nearest relative. Ramachandran is referring to Wernicke's area in the left temporal lobe (the area of the brain that is responsible for our comprehension of language -- where speech acquires meaning), the prefrontal cortex (an area responsible for decision-making and cognition, which includes the motor cortex where commands are sent to muscles for movement, and it includes Broca's area, which is responsible for speech), and the inferior parietal lobe (IPL). In humans, Ramachandran notes, the IPL evolved into two parts not found in apes --- the supramarginal gyrus (an area responsible for our ability to "visualize" words and action) and the angular gyrus (an area of the brain that Ramachandran says is connected to metaphor comprehension, but also finding a common denominator between two superficially dissimilar things). The genetic change that created these areas of the brain "rich in mirror neurons," surmises Ramachandran, "freed us from genetics by enhancing our ability to learn from one another" --- "liberat[ing] our brain from its Darwinian shackles, allowing the rapid spread of unique inventions" (tools, new words, constructing shelter, creating communities) that are at the foundation of culture. "Instead, increased sophistication of a single mechanism --- such as imitation and intention reading --- could explain the huge behavior gap between us and apes."
Ramachandran is a neuroscientist who has a wealth of clinical research observations about damage to specific areas of the brain and the consequences of that damage. And with that wealth, my appreciation for the role of specific areas of the brain and their connections to other areas of the brain during normal operations continued to grow. Other books, some of which are discussed in previous posts, have contributed to my appreciation, but Ramachandran's presentation in this book, including his drawings of the regions of the brain together with his glossary and specific case studies begins to put it all together. From a big picture point of view, with this book Ramachandran is pursuing the same subjects that Michael Gazzaniga pursued in examining what makes us "human" (see September 27, 2009 post) and that Antonio Damasio pursued in examining what creates our sense of self (see April 8, 2011 post). And Ramachandran contributes his own views on the origin of human language, a subject that was extensively reviewed in Christine Kenneally's The First Word (see August 31, 2009 post).
Let's discuss Ramanchandran on the evolution of language, because this is really the part of The Tell-Tale Brain that demonstrates what I have just said about this book. In discussing the evolution of language, Christine Kenneally reviews the views of Noam Chomsky (language is not the outcome of evolution, but is simply a built-in property of the brain), Stephen J. Gould (language initially evolved as a way to represent the world --- namely thinking about the world, and only later became a means of communication), and Steven Pinker (language is an instinct, an adaptation that is unique to humans that evolved specifically for communications purposes). Ramachandran does likewise, dismisses Chomsky quickly (his thesis cannot be tested), and then says that there is a grain of truth to both Gould and Pinker, but they just did not go far enough. For Ramanchandran, language did not evolve from some general mechanism for thinking, but neither did it evolve specifically for purposes of communication. What is innate and what evolved, says Ramachandran, is the competence to acquire rules of language. The actual acquisition of language occurs as a result of social interaction. Ramachandran believes that language was enabled by cross linkages in the brain between different motor maps (e.g. the area responsible for manual gestures and the area responsible for orafacial movements). Ramachandran calls this synkinesia ("together" "movement"), but he is borrowing from research on synesthesia, a brain phenomenon where senses are joined by cross-activation of two sensory maps. Thus what humans have is a built-in capacity to for translating gestures (movement) into words. The original "words," if you will, may have been grunts or other noises that accompanied a gesture (a proto-language). Synkinesia alone probably does not explain speech and language, but the human capacity for mimicry is critical as well, and hence the subject of mirror neurons enters the discussion of speech development, and again we return to the linkages between Broca's area, Wernicke's area, and the supramarginal gyrus and the angular gyrus in the IPL that enable what Ramachandran labels "cross-modal abstraction."
Ramachandran borrows from Gould the latter's concept of exaptation. An adaptation is an evolutionary response to natural selection. An exaptation is a refinement of an adaptation whereby a function is borrowed and used for a different function. Ramachandran believes that the IPL did not evolve for higher forms of abstraction such as giving names (words) to something, but evolved to provide hominids for refined interaction between vision and muscle and joint position while negotiating branches on tree top, a type of cross-modal abstraction. A subsequent exaptation was the development of these areas of the brain --- and their capacity for abstraction --- to develop tools and subassemblies of tools (e.g. an axehead and a suitably designed handle), says Ramachandran. He sees "a tantalizing resemblance" between the wielding of a tool made from composite parts and a full blown sentence including noun phrases and verbs. Speech, including syntax, emerged from the area of the brain that was key to tool manufacture, he speculates, and this became Broca's area. Add to that the areas of the parietal lobe (Wernicke's area and the IPL) and the human brain now has a language acquisition device. By the end of his discourse, Ramachandran concedes that he has been speculating on the evolution of language and thought, and he still has not resolved it, but he believes that it is not inconsistent with what neurologists know about patients who are damaged in these areas of the brain, and what we know about the evolution of other body parts. The problem is that language and abstraction are "software," and they can't be found in the fossil record that is all we have to understand what happened tens and hundreds of thousands of years ago. Unlike Christine Kenneally, Ramachandran does not discuss the debate over the FOXP2 gene and its possible connection to human language. Ramachandran asks, why were genes for language competence selected, but he does not illuminate what those genes might be., and perhaps that is because he recognizes that language is the outcome a several different modules in the brain, and there can be no single gene that would explain that fact.
There is much more to this book than just mirror neurons and the evolution of language, but there are discussions of memory, brain plasticity, the self, and free-will. Marco Iacoboni believes that, in view of research on mirror neurons and social behavior, the concepts of the self and free-will are blurred --- at least our Western sense of the individual is not as real as we sometimes think. (See September 18, 2009 post). Just how "free" and unique are we? he asks: Self and other are inextricably blended, says Iacoboni, and our behavior is subtly influenced by mirror neurons which produce automatic imitative influences based on what others are doing or saying. Iacoboni believes we have only "limited autonomy." Ramachandran does not touch this subject, but he does profess that humans have a sense of agency --- a desire to act and our belief in our ability to perform that act. Ramachandran says that there is evidence that the anterior cingulate in the frontal lobe is involved with wanting and intention. Damage to this area leads to apathy. The anterior cingulate, says Ramachandran, receives inputs from the parietal lobe, including the supramarginal gyrus, which as noted above, is involved with our ability to conjure up images of action (movement). These connections lead Ramachandran to believe there may be a neurological basis for free-will, signifying that it is not just a philosophical problem.
Ramachandran summarizes the current state of neuroscience with a comparison to chemistry: neuroscience is now at about the same stage that chemistry was in the 19th century, discovering the basic elements, grouping them into categories, and studying their interactions. As neuroscientists "map" the brain, they are "grouping their way toward the periodic table" of elements, but are not anywhere near atomic theory. As I noted in a previous post (see January 21, 2011 post and April 8, 2011 post), this is not fatal to the proposition that the era of skepticism is over. Ramachandran notes numerous experiments that remain to be started that would confirm one hypothesis or another.
And a final note. While Ramachandran failed to provide specific insight into how the brain creates art or fiction, on reflection, the elements of that mechanism may very well have been covered. We are, after all, talking about imagination, and the parts of the brain that enable abstraction, when combined with the parts of the brain that enable language (not just speech, but semantic content as well), when combined with the parts of the brain that enable us assemble things and to mimic what others do, must be involved in the creation of fiction and other forms of art that are the production of imagination.
Tuesday, September 20, 2011
Daniel Schacter, The Seven Sins of Memory (2001)
I started this blog, in small part, because I could not always recall when I read a book and what I got out of it. I thought about making notes in a notebook, like I did in college, and thought why not a digital notebook? The subject memory has continuously popped up in my postings, as the previous post recalls. In The Seven Sins of Memory, Harvard psychologist Daniel Schacter explains why I can't recall when I read a particular book and other failings of the human memory. And it's not all bad. In fact, Schacter says it's OK to forget. It's common. It's natural.
A clever title. Like the "seven deadly sins," the title is not an allusion to sinful behavior. It is a reference to our vulnerabilities and imperfections. Seven imperfections of memory: transience (memory that fades with the passage of time); absent-mindedness (rapid forgetting due to attentional lapses); blocking (hopefully a merely temporal phenomenon, like the name on the tip of your tongue that you can't remember); misattribution (mistaken identification); suggestibility (tendency to incorporate misleading information from external sources by suggestion into personal recollections); bias (five tendencies in which we generalize to reduce dissonance, reconstruct the past to fit the present, organize and regulate our mental life, and categorize; and persistence (remembering things we really want to forget).
All of us are familiar with and have experienced most, if not all of these imperfections of our memory. Some memories are encoded and "stick." Eric Kandel and others have described to us much of the biological basis about why we understand certain memories stay around longer than others --- long term potentiation. But not all memories stick. Some memories disappear immediately (absent-mindedness, because encoding fails due to divided attention); other memories stick, but are not retrievable --- sometimes for reasons we still do not fully understand --- but sometimes because we have little opportunity ever to recall a personal experience or piece of knowledge again and we forget(transience). And some memories are simply not accurate --- misidentification due to the inability to have specific recall of people or events that we are generally familiar with, or revised because external sources of information suggest to us that something different occurred, or biasing influences.
The bias influence is something we are already familiar with from Michael Shermer's book, The Believing Brain. (See June 12, 2011 post). What Shermer called the "confirmatory bias," Schacter refers to as the "consistency bias," where we infer past beliefs from our current state. This bias promotes psychological stability, perhaps avoiding cognitive dissonance. Similarly, hindsight bias, Schacter says, is ubiquitous, and reconstructs past to fit the present. What Shermer called the "self justification" bias, Schacter labels the "egocentric bias" that gives more credence to our own recollection of events --- reflecting the role of "self" in organizing and regulating our mental life. Studies show that when the mind encodes new information by relating it to the self, subsequent memory improves. Finally, the "stereotypical bias" reflects the minds tendency to categorize. What Shermer failed to address is the neurobiological basis for these biases. Schacter tries to address this, and, not surprisingly, calls on research by Michael Gazzaniga (see September 27, 2009 post) to explain it. The source of bias probably begins in the left hemisphere of the brain, which is adept at coming up with explanations and rationalizations for situations. This is the region where Gazzaniga's "interpreter" resides, the area responsible for language and symbols. The left hemisphere is responsible for inferences and generalizations to relate past and present. It draws on general knowledge and past experience to bring order to our psychological world. In contrast, the right hemisphere is where images and spatial location are prominent. The right hemisphere has a proclivity to respond on a literal basis to our environment, and acts as a check on the generalization of the left hemisphere. The left hemisphere probably contributes to consistency bias, hindsight bias, and egocentric bias. The left hemisphere is where our storytelling capacity resides. It is also where memories may be strengthened. Thinking and talking about our experiences changes the likelihood of subsequent remembering, reducing transience: elaborate encoding occurs to create memory.
I am reminded of an article by Joseph LeDoux of New York University in The Scientist back in 2009, entitled "Manipulating Memory." LeDoux reports on work that supports a theory of "reconsolidation" whereby memories are updated and influenced by new information. In other words, once a memory is recalled it is in a fragile state, and iit s susceptible to disruption by the very act of remembering so that what is "remembered" is not the same as what was experienced at the time of the event recalled. Several of Schacter's "sins" seem to support this view of human memory that it is neither fixed nor permanent.
These vulnerabilities of memory are not design flaws. They are likely by-products of of adaptive features of memory that have, in the long-run, served human memory well. Schacter reminds me of Antonio Damasio's reliance on the concept of homeostasis (see April 8, 2011 post) when he refers to the brain's "trade-off" between reducing the need to access information that is not needed or has not been needed and the cost of forgetting. The brain has adapted to an equilibrium condition. Transience occurs because there is little utility in storing unimportant, noncurrent information. Retrieval of "too much information" (data overload) has negative consequences and sacrifices abstract thinking. The brain does go on to autopilot --- repetitive events are handled by automatic processes, freeing up the brain's ability to devote attention to things with consequences; as a consequence occasional absent-minded errors occur when the mind is focused on something else, a small cost for the larger benefit of being able to pay attention. Memory sometimes operates because cues trigger recall. Contrary to some popular philosophers, David Hume's associationism is not dead. (See February 27, 2011 post).
The ability to record (encode) the gist of what happens and not every detail is a strength of memory, says Schacter. This capacity is fundamental to categorizing and comprehending and allows us to generalize across experiences without dwelling on details. Misattribution (false recognition) is probably a price we pay for the benefit of generalization. Generalizing, as discussed above, also leads to biases. Some features of memory are adaptations in evolutionary terms -- larger hippocampuses that facilitate finding stored food, and the amygdala that plays a role in emotional conditioning (contributing to the sin of "persistence"). But several features of our memory are unintended by-products of an existing feature or functionality of the brain. Schacter postulates that aspects of memory are what Stephen J. Gould referred to as "exaptations," features co-opted from an existing function that enhance fitness, but were not built by natural selection. Biases, Schacter concludes, are an incidental by-product of general knowledge and beliefs; blocking, absent-mindedness, misattribution, and suggestibility are exaptations of a memory system that does not routinely preserve all details required to specify the source of an experience.
There are practical concerns that arise from the learning in this book. The "sins" of misattribution, suggestibility, and bias all have implications for our justice system -- particularly criminal justice. Eyewitness misidentification, false confessions, witnesses influenced by suggestive questioning that retrieves a memory that does not match the actual experience are particularly worrisome. Law enforcement has taken notice and is learning from this research.
That we recognize that human memory is vulnerable, and that it is neither fixed nor permanent, informs us with respect to our history as well. While there are histories that are literally revisionist histories --- Schacter cites George Orwell's 1984 where a totalitarian government deliberately revises the past to suit the present --- our oral and written histories are known to have been revised to suit a current agenda. Knowing that "gospels" are the product of human writers, editors and redacters, it is difficult to understand why some have difficulty in acknowledging that the stories in these gospels suffer from the same vulnerabilities that human memory suffers. There are undoubtedly other psychological states that produce such difficulty.
A clever title. Like the "seven deadly sins," the title is not an allusion to sinful behavior. It is a reference to our vulnerabilities and imperfections. Seven imperfections of memory: transience (memory that fades with the passage of time); absent-mindedness (rapid forgetting due to attentional lapses); blocking (hopefully a merely temporal phenomenon, like the name on the tip of your tongue that you can't remember); misattribution (mistaken identification); suggestibility (tendency to incorporate misleading information from external sources by suggestion into personal recollections); bias (five tendencies in which we generalize to reduce dissonance, reconstruct the past to fit the present, organize and regulate our mental life, and categorize; and persistence (remembering things we really want to forget).
All of us are familiar with and have experienced most, if not all of these imperfections of our memory. Some memories are encoded and "stick." Eric Kandel and others have described to us much of the biological basis about why we understand certain memories stay around longer than others --- long term potentiation. But not all memories stick. Some memories disappear immediately (absent-mindedness, because encoding fails due to divided attention); other memories stick, but are not retrievable --- sometimes for reasons we still do not fully understand --- but sometimes because we have little opportunity ever to recall a personal experience or piece of knowledge again and we forget(transience). And some memories are simply not accurate --- misidentification due to the inability to have specific recall of people or events that we are generally familiar with, or revised because external sources of information suggest to us that something different occurred, or biasing influences.
The bias influence is something we are already familiar with from Michael Shermer's book, The Believing Brain. (See June 12, 2011 post). What Shermer called the "confirmatory bias," Schacter refers to as the "consistency bias," where we infer past beliefs from our current state. This bias promotes psychological stability, perhaps avoiding cognitive dissonance. Similarly, hindsight bias, Schacter says, is ubiquitous, and reconstructs past to fit the present. What Shermer called the "self justification" bias, Schacter labels the "egocentric bias" that gives more credence to our own recollection of events --- reflecting the role of "self" in organizing and regulating our mental life. Studies show that when the mind encodes new information by relating it to the self, subsequent memory improves. Finally, the "stereotypical bias" reflects the minds tendency to categorize. What Shermer failed to address is the neurobiological basis for these biases. Schacter tries to address this, and, not surprisingly, calls on research by Michael Gazzaniga (see September 27, 2009 post) to explain it. The source of bias probably begins in the left hemisphere of the brain, which is adept at coming up with explanations and rationalizations for situations. This is the region where Gazzaniga's "interpreter" resides, the area responsible for language and symbols. The left hemisphere is responsible for inferences and generalizations to relate past and present. It draws on general knowledge and past experience to bring order to our psychological world. In contrast, the right hemisphere is where images and spatial location are prominent. The right hemisphere has a proclivity to respond on a literal basis to our environment, and acts as a check on the generalization of the left hemisphere. The left hemisphere probably contributes to consistency bias, hindsight bias, and egocentric bias. The left hemisphere is where our storytelling capacity resides. It is also where memories may be strengthened. Thinking and talking about our experiences changes the likelihood of subsequent remembering, reducing transience: elaborate encoding occurs to create memory.
I am reminded of an article by Joseph LeDoux of New York University in The Scientist back in 2009, entitled "Manipulating Memory." LeDoux reports on work that supports a theory of "reconsolidation" whereby memories are updated and influenced by new information. In other words, once a memory is recalled it is in a fragile state, and iit s susceptible to disruption by the very act of remembering so that what is "remembered" is not the same as what was experienced at the time of the event recalled. Several of Schacter's "sins" seem to support this view of human memory that it is neither fixed nor permanent.
These vulnerabilities of memory are not design flaws. They are likely by-products of of adaptive features of memory that have, in the long-run, served human memory well. Schacter reminds me of Antonio Damasio's reliance on the concept of homeostasis (see April 8, 2011 post) when he refers to the brain's "trade-off" between reducing the need to access information that is not needed or has not been needed and the cost of forgetting. The brain has adapted to an equilibrium condition. Transience occurs because there is little utility in storing unimportant, noncurrent information. Retrieval of "too much information" (data overload) has negative consequences and sacrifices abstract thinking. The brain does go on to autopilot --- repetitive events are handled by automatic processes, freeing up the brain's ability to devote attention to things with consequences; as a consequence occasional absent-minded errors occur when the mind is focused on something else, a small cost for the larger benefit of being able to pay attention. Memory sometimes operates because cues trigger recall. Contrary to some popular philosophers, David Hume's associationism is not dead. (See February 27, 2011 post).
The ability to record (encode) the gist of what happens and not every detail is a strength of memory, says Schacter. This capacity is fundamental to categorizing and comprehending and allows us to generalize across experiences without dwelling on details. Misattribution (false recognition) is probably a price we pay for the benefit of generalization. Generalizing, as discussed above, also leads to biases. Some features of memory are adaptations in evolutionary terms -- larger hippocampuses that facilitate finding stored food, and the amygdala that plays a role in emotional conditioning (contributing to the sin of "persistence"). But several features of our memory are unintended by-products of an existing feature or functionality of the brain. Schacter postulates that aspects of memory are what Stephen J. Gould referred to as "exaptations," features co-opted from an existing function that enhance fitness, but were not built by natural selection. Biases, Schacter concludes, are an incidental by-product of general knowledge and beliefs; blocking, absent-mindedness, misattribution, and suggestibility are exaptations of a memory system that does not routinely preserve all details required to specify the source of an experience.
There are practical concerns that arise from the learning in this book. The "sins" of misattribution, suggestibility, and bias all have implications for our justice system -- particularly criminal justice. Eyewitness misidentification, false confessions, witnesses influenced by suggestive questioning that retrieves a memory that does not match the actual experience are particularly worrisome. Law enforcement has taken notice and is learning from this research.
That we recognize that human memory is vulnerable, and that it is neither fixed nor permanent, informs us with respect to our history as well. While there are histories that are literally revisionist histories --- Schacter cites George Orwell's 1984 where a totalitarian government deliberately revises the past to suit the present --- our oral and written histories are known to have been revised to suit a current agenda. Knowing that "gospels" are the product of human writers, editors and redacters, it is difficult to understand why some have difficulty in acknowledging that the stories in these gospels suffer from the same vulnerabilities that human memory suffers. There are undoubtedly other psychological states that produce such difficulty.
Sunday, August 28, 2011
William Shakespeare, King Lear (1607)
The most powerful of human senses is vision. For this reason, it is perhaps not surprising that that some of the most powerful stories of the human condition conceived by human storytellers involve tales of blindness. King Lear is such a story.
Ironically, one of the greatest fictional stories of the human condition -- the Genesis story (chs. 1-3) --- connects The Fall, not to blindness, but to sightedness. As Robert Alter explains in his translation of Genesis, succumbing to desire and "lust," the primordial humans, Adam and Eve, ate the fruit of a tree ('that it was lust to the eyes and the tree was lovely to look at") in the Garden of Eden, "[a]nd the eyes of the two [Adam and Eve] were opened, and they knew they were naked, and they sewed fig leaves and they made themselves loincloths." Through sightedness, they acquired knowledge: by the word of the serpent, knowledge of good and evil. But that is not the entire story. Sightedness is a consequence of failing to observe a god's commandment ("You shall not eat from it, and you shall not touch it lest you die.") With their condition of sightedness, Adam and Eve are expelled from a world of perfection and forced to till the soil to survive in a world of imperfection and scarce resources. Generations of jealousy, murder, and deception ensue. Hence, The Fall.
King Lear flips the Genesis story. Lear is, like much of mankind, fallen. Among his catalogue of failings, he solicits flattery. One who flatters offers insincere praise. One who solicits flattery is arguably involved in a pleasing form of self-deception. And self-deception is a form of blindness, the condition of which Lear suffers. Soliciting flattery from his two eldest daughters, Lear is pleased, and rewards them with a share of his kingdom as he prepares to withdraw from ruling. His youngest daughter, Cordelia, offers him only a sincere expression of her undying love, but not flattery. Lear cannot see her genuine love. Because of Lear's blindness, Cordelia is expelled from Lear's kingdom and flees to France. We have Genesis inverted: Man expelled from god's kingdom because he failed to observe the commandment of a "superior" and consequently, he "sees"; generations of deception ensue his failure to please his superior; by contrast, in Lear, we have a man who controls a human kingdom suffers a blinding, deceptive condition in the form of self-flattery, and expels his daughter, who seems wiser in her young years than her elder father, from his kingdom because she fails to please her father.
The Earl of Kent endeavors to salvage the relationship before it is too late, but Lear tells Kent, "Out of my sight," and Kent responds, "See better Lear, and let me still remain the true blank of thine eye." But Lear cannot distinguish genuine love from insincere forms of adulation. Oblivious to the conspiracy of his family and others around him, murder and suicide follow. In Genesis, blindness is a blessing; in King Lear, it is a curse.
The parallel story within the story of the Earl of Gloucester features a father who cares for his bastard son and is deceived by his true son, Edmund, to believe that the bastard Edgar is out to kill him. Gloucester takes up the cause of Lear and is declared a traitor by Lear's eldest daughters and their husbands. One husband, the Duke of Cornwall, gouges out both of Gloucester's eyes, leaving him completely blind. Where King Lear is the blind victim of self-deception, Gloucester is the blind victim of another's deception.
For both of these "blind" elders, Shakespeare awakens them with their other senses. Gloucester is offered assistance by a man who has been a tenant on his properties. Gloucester rejects the aid, and the tenant explains, "You cannot see your way." Gloucester replies, "I have no way and therefore want no eyes. I stumbled when I saw." We never heard a similar admission from Adam in Genesis. Remorseful that he mistakenly believed his bastard son Edgar intended him harm, Gloucester adds, "O dear son Edgar, the food of thy abused father's wrath! Might I but live to see in thy touch, I'd say I had eyes again."
Lear later says to Gloucester, "Read," and Gloucester responds, "With the case of eyes?." Lear: "Oho, are you there with me? No eyes in your head nor no money in your purse? Your eyes are in a heavy case, your purse in a light, yet you see how this world goes." Gloucester: "I see it feelingly." Lear: "What, art mad? A man may see how this world goes with no eyes. Look with thine ears. See how yond justice rails upon yond simple thief. . . . Get these glass eyes, And like a scurvy politician seem to see things thou dost not."
Sightedness leads the human condition to blindness, and to recover, survive and find justice we are compelled to rely on other senses -- touch, hearing, and feeling. Despite our blindness, we can still "see how this world goes." Gloucester dies, as do Lear's daughters, including Cordelia, one son-in-law, Cornwall, and Gloucester's son Edmund, and ultimately Lear succumbs. The survivors include Gloucester's bastard son Edgar, and the Earl of Kent, who successfully concealed himself from Lear and others in order to survive. There is no happy resolution here, but the decent characters who suffered not from blindness or self-deception do live to tell the tale.
So which is an affliction: sightedness or blindness? In Jose Saramago's novel Blindness, it is blindness that is an affliction and it is sightedness that is able influence justice and offer hope. The answer to the question will depend on the story an author wants to tell. For Shakespeare, blindness is likewise the affliction, but it is our other senses that enable us to see when our sight cannot. It should be no surprise that our greatest stories revolve around an appreciation and explication of the senses and feelings, which are at the core of our self. (See April 8, 2011 post (Damasio) and February 27, 2011 post (Hume)).
Ironically, one of the greatest fictional stories of the human condition -- the Genesis story (chs. 1-3) --- connects The Fall, not to blindness, but to sightedness. As Robert Alter explains in his translation of Genesis, succumbing to desire and "lust," the primordial humans, Adam and Eve, ate the fruit of a tree ('that it was lust to the eyes and the tree was lovely to look at") in the Garden of Eden, "[a]nd the eyes of the two [Adam and Eve] were opened, and they knew they were naked, and they sewed fig leaves and they made themselves loincloths." Through sightedness, they acquired knowledge: by the word of the serpent, knowledge of good and evil. But that is not the entire story. Sightedness is a consequence of failing to observe a god's commandment ("You shall not eat from it, and you shall not touch it lest you die.") With their condition of sightedness, Adam and Eve are expelled from a world of perfection and forced to till the soil to survive in a world of imperfection and scarce resources. Generations of jealousy, murder, and deception ensue. Hence, The Fall.
King Lear flips the Genesis story. Lear is, like much of mankind, fallen. Among his catalogue of failings, he solicits flattery. One who flatters offers insincere praise. One who solicits flattery is arguably involved in a pleasing form of self-deception. And self-deception is a form of blindness, the condition of which Lear suffers. Soliciting flattery from his two eldest daughters, Lear is pleased, and rewards them with a share of his kingdom as he prepares to withdraw from ruling. His youngest daughter, Cordelia, offers him only a sincere expression of her undying love, but not flattery. Lear cannot see her genuine love. Because of Lear's blindness, Cordelia is expelled from Lear's kingdom and flees to France. We have Genesis inverted: Man expelled from god's kingdom because he failed to observe the commandment of a "superior" and consequently, he "sees"; generations of deception ensue his failure to please his superior; by contrast, in Lear, we have a man who controls a human kingdom suffers a blinding, deceptive condition in the form of self-flattery, and expels his daughter, who seems wiser in her young years than her elder father, from his kingdom because she fails to please her father.
The Earl of Kent endeavors to salvage the relationship before it is too late, but Lear tells Kent, "Out of my sight," and Kent responds, "See better Lear, and let me still remain the true blank of thine eye." But Lear cannot distinguish genuine love from insincere forms of adulation. Oblivious to the conspiracy of his family and others around him, murder and suicide follow. In Genesis, blindness is a blessing; in King Lear, it is a curse.
The parallel story within the story of the Earl of Gloucester features a father who cares for his bastard son and is deceived by his true son, Edmund, to believe that the bastard Edgar is out to kill him. Gloucester takes up the cause of Lear and is declared a traitor by Lear's eldest daughters and their husbands. One husband, the Duke of Cornwall, gouges out both of Gloucester's eyes, leaving him completely blind. Where King Lear is the blind victim of self-deception, Gloucester is the blind victim of another's deception.
For both of these "blind" elders, Shakespeare awakens them with their other senses. Gloucester is offered assistance by a man who has been a tenant on his properties. Gloucester rejects the aid, and the tenant explains, "You cannot see your way." Gloucester replies, "I have no way and therefore want no eyes. I stumbled when I saw." We never heard a similar admission from Adam in Genesis. Remorseful that he mistakenly believed his bastard son Edgar intended him harm, Gloucester adds, "O dear son Edgar, the food of thy abused father's wrath! Might I but live to see in thy touch, I'd say I had eyes again."
Lear later says to Gloucester, "Read," and Gloucester responds, "With the case of eyes?." Lear: "Oho, are you there with me? No eyes in your head nor no money in your purse? Your eyes are in a heavy case, your purse in a light, yet you see how this world goes." Gloucester: "I see it feelingly." Lear: "What, art mad? A man may see how this world goes with no eyes. Look with thine ears. See how yond justice rails upon yond simple thief. . . . Get these glass eyes, And like a scurvy politician seem to see things thou dost not."
Sightedness leads the human condition to blindness, and to recover, survive and find justice we are compelled to rely on other senses -- touch, hearing, and feeling. Despite our blindness, we can still "see how this world goes." Gloucester dies, as do Lear's daughters, including Cordelia, one son-in-law, Cornwall, and Gloucester's son Edmund, and ultimately Lear succumbs. The survivors include Gloucester's bastard son Edgar, and the Earl of Kent, who successfully concealed himself from Lear and others in order to survive. There is no happy resolution here, but the decent characters who suffered not from blindness or self-deception do live to tell the tale.
So which is an affliction: sightedness or blindness? In Jose Saramago's novel Blindness, it is blindness that is an affliction and it is sightedness that is able influence justice and offer hope. The answer to the question will depend on the story an author wants to tell. For Shakespeare, blindness is likewise the affliction, but it is our other senses that enable us to see when our sight cannot. It should be no surprise that our greatest stories revolve around an appreciation and explication of the senses and feelings, which are at the core of our self. (See April 8, 2011 post (Damasio) and February 27, 2011 post (Hume)).
Monday, August 15, 2011
James Gleick, The Information (2011)
If there is one book that touches so many of the posts in this blog, it is James Gleick's The Information. Covering much of the territory as the two books covered by the first two posts --- Seth Lloyd's Programming the Universe (August 17, 2009 post) and Charles Seife's Decoding the Universe (August 23, 2009 post) --- including the physical nature of information, the relevance of the laws of thermodynamics to information theory, as well as the exploits of World War II codebreakers and the story of information theory developed by Claude Shannon and others --- Gleick also covers the history of information storage and transmission from the beginning of recorded history to Google. And there is even a tip of the hat to John Banville's The Infinities, (see March 28, 2010 post, where I noted the novel's connections to Lloyd and Seife).
Much of The Information covers the history of the transmission of information from Sumerian times to the present. The media evolves from markings in the earth, to stone tablets, to paper wrapped in scrolls, to paper bound in book form, to rhythmic pulses of drums, to pulses of energy over electrical wire,to pulses of energy through the air. With Claude Shannon's revolutionary 1949 paper on a mathematical theory of communication, whose purpose was to address an engineering problem of "reproducing at one point either exactly or approximately a message selected at another point," the way we look at information transmission changed. As described in the August 23, 2009 post on Charles Seife's Decoding the Universe, Shannon understood that information could be measured and quantized, which would enable him to determine how much information could be transmitted through a given channel of transmission. Semantics and meaning are irrelevant to this exercise, but the measurements were extremely useful in solving various communications problems associated with telephone communications at the time and has likewise been useful in developing greater bandwidth so more information is capable of transmission at a given time from one point to another. Shannon also understood that information was physical and was subject to the laws of thermodynamics just as other physical features of the universe, and particularly the second law pertaining to entropy. (See August 17, 2009 post). Shannon further addressed the problem of "noise" in the communication channel that corrupted or interfered with information in transmission, and a mathematical means for filtering out that noise to determine probabilistically that the information received was the same as the information sent.
I have previously complained that whoever said that entropy refers to disorder did the world a disservice. (See August 17, 2009 post), and Gleick confirms that much confusion has ensued over the centuries in our discourse over the "second law" of thermodynamics because of the way entropy has been characterized. For those looking for some clarity about the principle of entropy, Gleick is worth reading. As initially conceived, entropy was a measure of the unavailability of energy for work because of dissipation. It referred to a "thermodynamic condition," where previously separate hot and cold bodies (could be a liquid or gas) generated steam that could be converted to energy for work, but once the hot and cold bodies mixed, the mixture achieved a uniform temperature and the amount of energy in steam dissipated making it unavailable for work. The "thermodynamic condition" that previously existed was said to have "dissipated," and there was no more energy available for work. The phrase "disorder" entered the picture because the previous thermodynamic condition where hot and cold bodies were separated and were capable of generating energy for work was considered "orderly," and the homogeneous mixture that was not capable of generating energy for work was considered "disorderly." The second law of thermodynamics stands for the proposition that the universe "tends" to flow from the orderly to the disorderly. Ironically, the "orderly" was viewed as a "less likely" macrostate, and the "disorderly" was viewed as a "more likely" macrostate. Probability theory therefore enters this discussion, and what is more probable is a homogeneous state where we are less likely to find separate distinct states.
Shannon's insight was that entropy was relevant to all dynamic systems, not just thermodynamics. To the physicist, entropy is a measurement of uncertainty about the state of a physical system. To the information theorist, entropy is a measure of uncertainty about a message, where it is less clear that the message that was transmitted is the same as the message that was received. Ironically, notes Gleick, humans, contrary to physical laws, seem bent on curbing entropy, making the environment in which they live, more orderly. We build things; we compile; we categorize; we separate. As Schrodinger noted, living things feed on negative entropy. The second law contemplates a closed system, and earth is not a closed system. Life feeds upon energy and negative entropy leaking into the earth's system. Similarly, humans have proven creative in dealing with probabilities and discerning information from communications that are not certain in order to make messages more certain and information theory provides us tools to do just that.
In contrast to Seth Lloyd and Charles Seife's works on the same subject, Gleick spends more time chronicling the technological development of information transmission. As I read on, I found myself thinking about a different subject to which Gleick gives only passing attention: memory. The subject of memory has been a continuous visitor to this blog, (See posts of September 9, 2010, September 28, 2010, November 27, 2010, and April 8, 2011). We tend to think of memory in terms of an information storage device. A 500 page book stores two million bits of information. A computer's hard drive or a CD-ROM store vastly more bits of information. These devices do not store words or images. They store information that encodes for words or images, but they also contain an electrical means for retrieving those images and words that are encoded. Thus a system of retrieving memory is essential to memory, otherwise it has no utility. This is entirely consistent with the description of the human brain's "architecture of memory" as described by Antonio Damasio. (See April 8, 2011 post). By Damasio's reckoning, the architecture of memory he describes evolved because of storage capacity limitations on our ability to retain images of prior events. Instead of files of memories of images and words, memory is found in the connections between cells in the brain. (See post of November 27, 2010). Shannon's research influenced the development of cognitive psychology, Gleick reports, because it became useful in understanding the limitations on our capacity to receive and store information, short-term and long-term memory, pattern recognition, attention, and problem solving.
Gleick does briefly allude to another subject that has received attention in prior posts: the human mind's capacity for storytelling and providing an explanation for what we experience, along the lines described by Michael Gazzaniga in Human. (See May 22, 2011 post and June 12 and June 28, 2011 posts). Storytelling has to be linked to memory formation and retrieval. Recording information, --- on sticks, on walls of caves, whatever --- says Gleick, "served as aids to memory." Homer's poetry, composed and sung in a mnemonic meter, "served first and foremost as an aid to memory." I think storytelling evolved in part to preserve our memory, but the irony is that those same stories can lead to distortions of the memory we try to preserve. Information is corrupted and does not copy accurately.
We have heard about this same sort of phenomenon in the context of the genome. (See November 27, 2010 post). The ultimate information storage device is the cell. The cell stores genetic material --- genes --- each of which is comprised of bits of information. At some point in evolutionary history, the means for communicating the information stored in the cell through replication became possible. Information contained in one information storage device was moved to another information storage device. Gleick quotes George Gamow: "The nucleus of a living cell is a storehouse of information," adding that it is a transmitter of information from which stems the continuity of life. Gamow described the study of genetics as the study of "the language of the cells." Matt Ridley (see November 27, 2010 post) would agree. When biologists discovered redundancy in the codons of the cell, they realized it was nature's way of dealing with "noise" in the transmission of information by providing tolerance for errors in transmission.
At some point in human evolution, external storage of information became important for survival. Gleick describes some of the earliest known examples of external information storage --- Sumerian cuneiform tablets recording contracts, governance documents, and business transactions. Interestingly, these "documents" memorialize agreements --- matters of consensus between two or more persons. These forms of external information storage are undoubtedly significant to early economic and political socialization. Human development of external information storage devices is unparalleled in the animal kingdom. From tablets, to papyrus, to paper, to the construction of libraries, to film and vinyl media, punch cards, optical and magnetic media, and semiconductors. But external information storage did not begin with out species. As Holldobler and Wilson documented in the case of the social insects: certain ants secrete pheromones in soil for colony ants to follow leaders from the nest to food sources and back. (See post of November 4, 2009). Soil becomes an information storage device. Urination by animals sometimes serves a social purpose to mark territory. Trees, plants, and soil become an information storage device. But this merely confirms my point about storytelling serving as an aid to memory. Sometimes that storytelling is an accurate, but memorable account of what really happened --- and we call that non-fiction. And other times it is exaggerated and manipulated to make it memorable --- and we call that fiction.
I want to close with two quotes that Gleick recites that say a little bit about what this book is about. From Claude Shannon: "The fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point. Frequently the messages have meaning." As Gleick recounts, Shannon was not interested much in meaning, but just being able to determine that the information sent was exactly or approximately the same as the message received. And "approximately" was good enough for Shannon, because his mathematical algorithms would filter out the noise to provide a probability of what the information was that was sent. If this sounds like the quantum world that was described in Quantum (see previous post), well it is. And Heisenberg's uncertainty principle and Godel's incompleteness theorem figure into information theory.
Gleick also quotes Seth Lloyd, whose book Programming the Universe, inaugurated this blog two years ago: "The more energy, the faster the bits flip. Earth, air, fire, and water in the end are all made of energy, but the different forms they take are determined by information. To do anything requires energy. To specify what is done requires information." This is a statement about the physicality of information, a subject that I have alluded to many times over the past two years in various posts.
Much of The Information covers the history of the transmission of information from Sumerian times to the present. The media evolves from markings in the earth, to stone tablets, to paper wrapped in scrolls, to paper bound in book form, to rhythmic pulses of drums, to pulses of energy over electrical wire,to pulses of energy through the air. With Claude Shannon's revolutionary 1949 paper on a mathematical theory of communication, whose purpose was to address an engineering problem of "reproducing at one point either exactly or approximately a message selected at another point," the way we look at information transmission changed. As described in the August 23, 2009 post on Charles Seife's Decoding the Universe, Shannon understood that information could be measured and quantized, which would enable him to determine how much information could be transmitted through a given channel of transmission. Semantics and meaning are irrelevant to this exercise, but the measurements were extremely useful in solving various communications problems associated with telephone communications at the time and has likewise been useful in developing greater bandwidth so more information is capable of transmission at a given time from one point to another. Shannon also understood that information was physical and was subject to the laws of thermodynamics just as other physical features of the universe, and particularly the second law pertaining to entropy. (See August 17, 2009 post). Shannon further addressed the problem of "noise" in the communication channel that corrupted or interfered with information in transmission, and a mathematical means for filtering out that noise to determine probabilistically that the information received was the same as the information sent.
I have previously complained that whoever said that entropy refers to disorder did the world a disservice. (See August 17, 2009 post), and Gleick confirms that much confusion has ensued over the centuries in our discourse over the "second law" of thermodynamics because of the way entropy has been characterized. For those looking for some clarity about the principle of entropy, Gleick is worth reading. As initially conceived, entropy was a measure of the unavailability of energy for work because of dissipation. It referred to a "thermodynamic condition," where previously separate hot and cold bodies (could be a liquid or gas) generated steam that could be converted to energy for work, but once the hot and cold bodies mixed, the mixture achieved a uniform temperature and the amount of energy in steam dissipated making it unavailable for work. The "thermodynamic condition" that previously existed was said to have "dissipated," and there was no more energy available for work. The phrase "disorder" entered the picture because the previous thermodynamic condition where hot and cold bodies were separated and were capable of generating energy for work was considered "orderly," and the homogeneous mixture that was not capable of generating energy for work was considered "disorderly." The second law of thermodynamics stands for the proposition that the universe "tends" to flow from the orderly to the disorderly. Ironically, the "orderly" was viewed as a "less likely" macrostate, and the "disorderly" was viewed as a "more likely" macrostate. Probability theory therefore enters this discussion, and what is more probable is a homogeneous state where we are less likely to find separate distinct states.
Shannon's insight was that entropy was relevant to all dynamic systems, not just thermodynamics. To the physicist, entropy is a measurement of uncertainty about the state of a physical system. To the information theorist, entropy is a measure of uncertainty about a message, where it is less clear that the message that was transmitted is the same as the message that was received. Ironically, notes Gleick, humans, contrary to physical laws, seem bent on curbing entropy, making the environment in which they live, more orderly. We build things; we compile; we categorize; we separate. As Schrodinger noted, living things feed on negative entropy. The second law contemplates a closed system, and earth is not a closed system. Life feeds upon energy and negative entropy leaking into the earth's system. Similarly, humans have proven creative in dealing with probabilities and discerning information from communications that are not certain in order to make messages more certain and information theory provides us tools to do just that.
In contrast to Seth Lloyd and Charles Seife's works on the same subject, Gleick spends more time chronicling the technological development of information transmission. As I read on, I found myself thinking about a different subject to which Gleick gives only passing attention: memory. The subject of memory has been a continuous visitor to this blog, (See posts of September 9, 2010, September 28, 2010, November 27, 2010, and April 8, 2011). We tend to think of memory in terms of an information storage device. A 500 page book stores two million bits of information. A computer's hard drive or a CD-ROM store vastly more bits of information. These devices do not store words or images. They store information that encodes for words or images, but they also contain an electrical means for retrieving those images and words that are encoded. Thus a system of retrieving memory is essential to memory, otherwise it has no utility. This is entirely consistent with the description of the human brain's "architecture of memory" as described by Antonio Damasio. (See April 8, 2011 post). By Damasio's reckoning, the architecture of memory he describes evolved because of storage capacity limitations on our ability to retain images of prior events. Instead of files of memories of images and words, memory is found in the connections between cells in the brain. (See post of November 27, 2010). Shannon's research influenced the development of cognitive psychology, Gleick reports, because it became useful in understanding the limitations on our capacity to receive and store information, short-term and long-term memory, pattern recognition, attention, and problem solving.
Gleick does briefly allude to another subject that has received attention in prior posts: the human mind's capacity for storytelling and providing an explanation for what we experience, along the lines described by Michael Gazzaniga in Human. (See May 22, 2011 post and June 12 and June 28, 2011 posts). Storytelling has to be linked to memory formation and retrieval. Recording information, --- on sticks, on walls of caves, whatever --- says Gleick, "served as aids to memory." Homer's poetry, composed and sung in a mnemonic meter, "served first and foremost as an aid to memory." I think storytelling evolved in part to preserve our memory, but the irony is that those same stories can lead to distortions of the memory we try to preserve. Information is corrupted and does not copy accurately.
We have heard about this same sort of phenomenon in the context of the genome. (See November 27, 2010 post). The ultimate information storage device is the cell. The cell stores genetic material --- genes --- each of which is comprised of bits of information. At some point in evolutionary history, the means for communicating the information stored in the cell through replication became possible. Information contained in one information storage device was moved to another information storage device. Gleick quotes George Gamow: "The nucleus of a living cell is a storehouse of information," adding that it is a transmitter of information from which stems the continuity of life. Gamow described the study of genetics as the study of "the language of the cells." Matt Ridley (see November 27, 2010 post) would agree. When biologists discovered redundancy in the codons of the cell, they realized it was nature's way of dealing with "noise" in the transmission of information by providing tolerance for errors in transmission.
At some point in human evolution, external storage of information became important for survival. Gleick describes some of the earliest known examples of external information storage --- Sumerian cuneiform tablets recording contracts, governance documents, and business transactions. Interestingly, these "documents" memorialize agreements --- matters of consensus between two or more persons. These forms of external information storage are undoubtedly significant to early economic and political socialization. Human development of external information storage devices is unparalleled in the animal kingdom. From tablets, to papyrus, to paper, to the construction of libraries, to film and vinyl media, punch cards, optical and magnetic media, and semiconductors. But external information storage did not begin with out species. As Holldobler and Wilson documented in the case of the social insects: certain ants secrete pheromones in soil for colony ants to follow leaders from the nest to food sources and back. (See post of November 4, 2009). Soil becomes an information storage device. Urination by animals sometimes serves a social purpose to mark territory. Trees, plants, and soil become an information storage device. But this merely confirms my point about storytelling serving as an aid to memory. Sometimes that storytelling is an accurate, but memorable account of what really happened --- and we call that non-fiction. And other times it is exaggerated and manipulated to make it memorable --- and we call that fiction.
I want to close with two quotes that Gleick recites that say a little bit about what this book is about. From Claude Shannon: "The fundamental problem of communication is that of reproducing at one point either exactly or approximately a message selected at another point. Frequently the messages have meaning." As Gleick recounts, Shannon was not interested much in meaning, but just being able to determine that the information sent was exactly or approximately the same as the message received. And "approximately" was good enough for Shannon, because his mathematical algorithms would filter out the noise to provide a probability of what the information was that was sent. If this sounds like the quantum world that was described in Quantum (see previous post), well it is. And Heisenberg's uncertainty principle and Godel's incompleteness theorem figure into information theory.
Gleick also quotes Seth Lloyd, whose book Programming the Universe, inaugurated this blog two years ago: "The more energy, the faster the bits flip. Earth, air, fire, and water in the end are all made of energy, but the different forms they take are determined by information. To do anything requires energy. To specify what is done requires information." This is a statement about the physicality of information, a subject that I have alluded to many times over the past two years in various posts.
Saturday, July 30, 2011
Manjit Kumar, Quantum (2008)
A theme running through several of this year's posts is the role of human imagination in aesthetics, creating works of fiction, rewriting history, creating sacred texts, as well as in science, and the neuroscience that explains the biology of imagination. We tend to think that scientific research and analysis is all about uncovering what is "real," identifying objectively verifiable facts that are observable to our senses and are widely accepted as true. This is conventional wisdom, but human imagination plays a key role in uncovering what is real and is a core feature of scientific inquiry. Much of what scientific inquiry is directed at, particularly in physics, is the stuff we cannot see --- it is either too small to be detected by our senses, even aided by the latest technological tools that enable us to detect or observe the very small, or it is too far away (in either time or space) or too large to see or comprehend. Inquiry into the very small or the very distant begins with imagination, sometimes called theory, which is hopefully both internally consistent as well as externally consistent with the things we can observe. Consensus over theory typically does not always develop quickly, and it sometimes involves substantial disputes. In scientific inquiry, theory is typically followed by developing experiments that seek to confirm or disprove what the imagination has created. Sometimes those experiments take only a few weeks or months to confirm or disprove the theory; sometimes those experiments follow the development of the theory by decades. Manjit Kumar provides a peek into this process in his book Quantum.
At the beginning of the 20th century, physicists studying light, heat, color and electromagnetism realized that the physical world we think we actually see does not conveniently coincide with the physical world that we do not see. We see a beam of light or we feel the radiation of heat and we sense a continuous emission and absorption of light or heat. But is it continuous? The prevailing wisdom was that radiated energy was emitted as a continuous wave and that changes in heat, energy and color were believed to be explained by changes in the amplitude or frequency of the wave. Max Planck discovered that this was not possible. Energy either increases or decreases discontinuously, and, contrary to the prevailing wisdom, Planck was forced to imagine that energy is released or absorbed in packets --- what he called "quanta." The reason we cannot see these packets is because the increase or decrease in energy occurs in very small steps (6.626 divided by one thousand trillion trillion), a number that is now known as Planck's constant. These steps are so small they cannot be observed. Experiments subsequently confirmed Planck's theory. A few years later, Albert Einstein extended Planck's conclusions to light in his 1905 paper on the photoelectric effect: while light depends on wavelength and frequency, all electromagnetic radiation actually travels in a stream of tiny "light-quanta," later called photons.
Although the notion that at its most fundamental level reality was based on tiny atoms had been around since classical Greece, atomism was never seriously developed in science until the 19th century. Einstein and Planck's work accelerated modern atomic theory. During the first three decades of the 20th century, the basic structure of the atom and the behavior of electrons was close to being fully developed. Ernest Rutherford and Niels Bohr were hugely responsible for this work. Bohr introduced the idea that as an electron orbiting the atomic nucleus dropped from a higher energy orbit to a lower energy orbit, a photon (a quantum of energy) was released and spectral light is produced. This has been referred to as a quantum leap. Beginning with Planck and Einstein and developed further by Rutherford, Bohr, Max Born, Werner Heisenberg, Wolfgang Pauli, Louis de Broglie and others, this concept of physical reality became known as quantum mechanics, as distinct from classical physics initially developed by Isaac Newton.
The subtitle of Kumar's book is "Einstein, Bohr, and the great debate about the nature of reality." The "great debate" ironically did not dispute the theory of quantum mechanics. Yes, there were debates along the way as the unexplained attributes of quantum theory were worked out, and one of those debates was whether quantum theory left any room for classical Newtonian physics. Another debate was whether physics was constrained to what could be known and observed. Emerging from the latter debate is Werner Heisenberg's now-famous uncertainty principle, which establishes that it is not possible to simulaneously measure two or more complementary variables --- in the case of an electron, its momentum and location. It is only possible to measure one of them accurately at a given point in time. And there have been further debates about the meaning or significance of uncertainty relations: does it mean that we can never predict causal relations? Or is the meaning of the principle confined to a problem of measurement? To Bohr, quantum mechanics took on a probabilistic character where "only the probability of a given outcome among a range of possibilities can be predicted."
The "great debate" was over the question of whether quantum theory was "complete." Bohr claimed that it was. Einstein had his doubts. Einstein believed that quantum mechanics was observer dependent, and that the act of measuring physical pheonemana interfered with our understanding of reality. In Einstein's view, reality was observer-independent --- yes, trees fall in the forest when there is no one around to watch them fall. From Einstein's perspective, a "complete" theory of physics should be able to describe reality without creating the uncertainty relations created by the observer of reality: physics ought to be able to explain causal relations without having to rely on probabilistic assessments over a range of possibilities, although later Einstein dropped his criticism on quantum mechanics' focus on probabilities. From the 1920s through the early 1950s, Einstein and Bohr politely and professionally debated the completeness of quantum mechanics and whether it truly described reality. The debate was never fully settled during their lifetime, nor has it been settled thereafter.
The difference between the two men was even deeper however. As Kumar explains, for Bohr quantum mechanics was not a description of reality. "There is no quantum world," Bohr declared. "There is only an abstract mechanical description. It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature." For Bohr, physics was an observer-dependent exercise aimed at explaining what we could about nature in our own terms. Einstein disagreed. He believed there was an observer-independent reality, and physics "has the sole purpose of determining what is."
Einstein, notes Kumar, never put forward his own theory about the nature of reality. He challenged Bohr, not with facts or data, but with a number of "thought experiments" that would purport to undercut an aspect of quantum mechanics. Bohr would parry with rebuttal that would undermine Einstein's thought experiement. These were mind games among bright men. Kumar describes a conversation between Einstein and Heisenberg, in which the former probed the latter about the philosophical foundations of his work:
"You assume the existence of electrons inside the atom," said Einstein, "and you are probably right to do so. But you refuse to consider their orbits even though we can observe electron tracks in a cloud chamber. I should very much like to hear more about your reasons for making such strange assumptions." Heisenberg replied, "We cannot observe electron orbits inside the atom, but the radiation which the atom emits during discharges enables us to deduce the frequencies and corresponding amplitudes of its electrons. Since a good theory must be based on directly observable magnitudes, I thought it more fitting to restrict myself to these, treating them, as it were, as representatives of the electron orbits." Einstein reacted: "You don't seriously believe that none but observable magnitudes must go into a physical theory? It is quite wrong to try founding a theory on observable magnitudes alone. In reality the very opposite happens.
It is the theory which decides what we can observe."
This is a fascintating conversation. Kumar observes that 100 years earlier in 1830, Auguste Comte had argued that, "while every theory has to be based on observation, the mind also needs a theory in order to make observations." For Einstein, "A phenomenon under observation produces certain events in our measuring apparatus, which eventually produce sense impressions and help fix the effects in our consciousness." These effects, said Einstein, depend upon theories. Heisenberg appears to be taking the position of David Hume in the Treatise on Human Nature when he says "a good theory must be based on directly observable magnitudes." Hume wrote (see February 27, 2011 post), "Should it be demanded why men form general rules, and allow them to influence their judgment, even contrary to present observation and experience, I should reply, that in my opinion it proceeds from those very principles, on which all judgments concerning causes and effects depend. Our judgments concerning cause and effect are derived from habit and experience; and when we have been accustomed to see one object united to another, our imagination passes from the first to the second, by a natural transition, which precedes reflection [that is before we even seriously think about what we just experienced] and which cannot be prevented by it." Einstein, on the other hand, argues that it is a theory that decides what we can observe.
But what if the "theory" --- the means by which we explain our observations --- embraces probabilities? In other words, humans are capable of measuring directly some of our observations and "know" that measurement with relative certainty, but we cannot measure every observation and we are compelled to admit that we can only "probably" know what we have observed with respect to these other observations. Does this undermine what we can say is "real" or what we can claim is an objective reality? Even Hume appears to concede this limitation on our knowledge, and that probabilities are central to "beliefs." Would this not have been satisfactory to Einstein? Probably, says Kumar, who concludes that "Einstein accepted that quantum mechanics was the best theory available --- the only one which can be built out of the fundamental concepts of force and material points." But acceptance of quantum mechanics, for Einstein, was without prejudice to continue the search for the theory that explains everything, a theory that demystified the uncertainties that quantum mechanics was willing to leave unexplained. For Bohr, there was no reality beyond what could be observed and measured and there was no physical reality beyond what observation and measurement could account for. In this debate, Einstein clearly prevails. If Bohr prevails, we would never have spent millions of dollars looking for quarks, bosons, gluons, leptons, and smaller atomic units.
Imagination leads us into different directions. It can lead us closer to understanding and knowing a confirmable, accepted reality that we do not yet fully see, hear, smell, or feel because it is too small for our technologically-assisted senses to observe. It can also lead us to the realm of fantasy, fiction, and reinventing history. The "great debate" is a testament to imagination. Quantum mechanics powerfully explains physical pheonomenon in a way that has been confirmed by experiment. The "thought experiment" in science is nearly an exercise in pure imagination, not for the purpose of creating fantasy or fiction, but for the purpose of explaining what "is." Einstein understood that if the thought experiment is found wanting in the light of new experimental evidence, then the philosophical position it supports collapses with it.
At the beginning of the 20th century, physicists studying light, heat, color and electromagnetism realized that the physical world we think we actually see does not conveniently coincide with the physical world that we do not see. We see a beam of light or we feel the radiation of heat and we sense a continuous emission and absorption of light or heat. But is it continuous? The prevailing wisdom was that radiated energy was emitted as a continuous wave and that changes in heat, energy and color were believed to be explained by changes in the amplitude or frequency of the wave. Max Planck discovered that this was not possible. Energy either increases or decreases discontinuously, and, contrary to the prevailing wisdom, Planck was forced to imagine that energy is released or absorbed in packets --- what he called "quanta." The reason we cannot see these packets is because the increase or decrease in energy occurs in very small steps (6.626 divided by one thousand trillion trillion), a number that is now known as Planck's constant. These steps are so small they cannot be observed. Experiments subsequently confirmed Planck's theory. A few years later, Albert Einstein extended Planck's conclusions to light in his 1905 paper on the photoelectric effect: while light depends on wavelength and frequency, all electromagnetic radiation actually travels in a stream of tiny "light-quanta," later called photons.
Although the notion that at its most fundamental level reality was based on tiny atoms had been around since classical Greece, atomism was never seriously developed in science until the 19th century. Einstein and Planck's work accelerated modern atomic theory. During the first three decades of the 20th century, the basic structure of the atom and the behavior of electrons was close to being fully developed. Ernest Rutherford and Niels Bohr were hugely responsible for this work. Bohr introduced the idea that as an electron orbiting the atomic nucleus dropped from a higher energy orbit to a lower energy orbit, a photon (a quantum of energy) was released and spectral light is produced. This has been referred to as a quantum leap. Beginning with Planck and Einstein and developed further by Rutherford, Bohr, Max Born, Werner Heisenberg, Wolfgang Pauli, Louis de Broglie and others, this concept of physical reality became known as quantum mechanics, as distinct from classical physics initially developed by Isaac Newton.
The subtitle of Kumar's book is "Einstein, Bohr, and the great debate about the nature of reality." The "great debate" ironically did not dispute the theory of quantum mechanics. Yes, there were debates along the way as the unexplained attributes of quantum theory were worked out, and one of those debates was whether quantum theory left any room for classical Newtonian physics. Another debate was whether physics was constrained to what could be known and observed. Emerging from the latter debate is Werner Heisenberg's now-famous uncertainty principle, which establishes that it is not possible to simulaneously measure two or more complementary variables --- in the case of an electron, its momentum and location. It is only possible to measure one of them accurately at a given point in time. And there have been further debates about the meaning or significance of uncertainty relations: does it mean that we can never predict causal relations? Or is the meaning of the principle confined to a problem of measurement? To Bohr, quantum mechanics took on a probabilistic character where "only the probability of a given outcome among a range of possibilities can be predicted."
The "great debate" was over the question of whether quantum theory was "complete." Bohr claimed that it was. Einstein had his doubts. Einstein believed that quantum mechanics was observer dependent, and that the act of measuring physical pheonemana interfered with our understanding of reality. In Einstein's view, reality was observer-independent --- yes, trees fall in the forest when there is no one around to watch them fall. From Einstein's perspective, a "complete" theory of physics should be able to describe reality without creating the uncertainty relations created by the observer of reality: physics ought to be able to explain causal relations without having to rely on probabilistic assessments over a range of possibilities, although later Einstein dropped his criticism on quantum mechanics' focus on probabilities. From the 1920s through the early 1950s, Einstein and Bohr politely and professionally debated the completeness of quantum mechanics and whether it truly described reality. The debate was never fully settled during their lifetime, nor has it been settled thereafter.
The difference between the two men was even deeper however. As Kumar explains, for Bohr quantum mechanics was not a description of reality. "There is no quantum world," Bohr declared. "There is only an abstract mechanical description. It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature." For Bohr, physics was an observer-dependent exercise aimed at explaining what we could about nature in our own terms. Einstein disagreed. He believed there was an observer-independent reality, and physics "has the sole purpose of determining what is."
Einstein, notes Kumar, never put forward his own theory about the nature of reality. He challenged Bohr, not with facts or data, but with a number of "thought experiments" that would purport to undercut an aspect of quantum mechanics. Bohr would parry with rebuttal that would undermine Einstein's thought experiement. These were mind games among bright men. Kumar describes a conversation between Einstein and Heisenberg, in which the former probed the latter about the philosophical foundations of his work:
"You assume the existence of electrons inside the atom," said Einstein, "and you are probably right to do so. But you refuse to consider their orbits even though we can observe electron tracks in a cloud chamber. I should very much like to hear more about your reasons for making such strange assumptions." Heisenberg replied, "We cannot observe electron orbits inside the atom, but the radiation which the atom emits during discharges enables us to deduce the frequencies and corresponding amplitudes of its electrons. Since a good theory must be based on directly observable magnitudes, I thought it more fitting to restrict myself to these, treating them, as it were, as representatives of the electron orbits." Einstein reacted: "You don't seriously believe that none but observable magnitudes must go into a physical theory? It is quite wrong to try founding a theory on observable magnitudes alone. In reality the very opposite happens.
It is the theory which decides what we can observe."
This is a fascintating conversation. Kumar observes that 100 years earlier in 1830, Auguste Comte had argued that, "while every theory has to be based on observation, the mind also needs a theory in order to make observations." For Einstein, "A phenomenon under observation produces certain events in our measuring apparatus, which eventually produce sense impressions and help fix the effects in our consciousness." These effects, said Einstein, depend upon theories. Heisenberg appears to be taking the position of David Hume in the Treatise on Human Nature when he says "a good theory must be based on directly observable magnitudes." Hume wrote (see February 27, 2011 post), "Should it be demanded why men form general rules, and allow them to influence their judgment, even contrary to present observation and experience, I should reply, that in my opinion it proceeds from those very principles, on which all judgments concerning causes and effects depend. Our judgments concerning cause and effect are derived from habit and experience; and when we have been accustomed to see one object united to another, our imagination passes from the first to the second, by a natural transition, which precedes reflection [that is before we even seriously think about what we just experienced] and which cannot be prevented by it." Einstein, on the other hand, argues that it is a theory that decides what we can observe.
But what if the "theory" --- the means by which we explain our observations --- embraces probabilities? In other words, humans are capable of measuring directly some of our observations and "know" that measurement with relative certainty, but we cannot measure every observation and we are compelled to admit that we can only "probably" know what we have observed with respect to these other observations. Does this undermine what we can say is "real" or what we can claim is an objective reality? Even Hume appears to concede this limitation on our knowledge, and that probabilities are central to "beliefs." Would this not have been satisfactory to Einstein? Probably, says Kumar, who concludes that "Einstein accepted that quantum mechanics was the best theory available --- the only one which can be built out of the fundamental concepts of force and material points." But acceptance of quantum mechanics, for Einstein, was without prejudice to continue the search for the theory that explains everything, a theory that demystified the uncertainties that quantum mechanics was willing to leave unexplained. For Bohr, there was no reality beyond what could be observed and measured and there was no physical reality beyond what observation and measurement could account for. In this debate, Einstein clearly prevails. If Bohr prevails, we would never have spent millions of dollars looking for quarks, bosons, gluons, leptons, and smaller atomic units.
Imagination leads us into different directions. It can lead us closer to understanding and knowing a confirmable, accepted reality that we do not yet fully see, hear, smell, or feel because it is too small for our technologically-assisted senses to observe. It can also lead us to the realm of fantasy, fiction, and reinventing history. The "great debate" is a testament to imagination. Quantum mechanics powerfully explains physical pheonomenon in a way that has been confirmed by experiment. The "thought experiment" in science is nearly an exercise in pure imagination, not for the purpose of creating fantasy or fiction, but for the purpose of explaining what "is." Einstein understood that if the thought experiment is found wanting in the light of new experimental evidence, then the philosophical position it supports collapses with it.
Sunday, July 17, 2011
Jose Saramago, The Elephant's Journey (2008)
A portion of the oeuvre of Jose Saramago revolves around themes of life and death. But even in the context of a novel like All The Names , about the custodian of national records of birth and death, the story is really about a person's life. And as we just saw in the previous post discussing The Year of the Death of Ricardo Reis, the story of the last nine months of a man's life and his conversations with another man who has just died, the story is really about relationships among the living. In Saramago's Death With Interruptions, death takes a holiday and the religious institutions are confronted with the prospect of real eternal life, leading the institution to realize that if we don't start dying again "we have no future."
The Elephant's Journey, Saramago's final novel, published two years before he died in 2010, is not as philosophically deep as his earlier novels, but this story of an elephant's journey from India to Lisbon to Vienna during the 16th century --- a historical event fictionalized by Saramago, because there is no detailed record of the journey that has been left behind --- ends in the death of the elephant two years after his arrival in Vienna. For Saramago, however, the elephant's death merely affirms life and our memory of life: the Austrian Archduke Maximilian, who received the elephant as a gift from King Joao III of Portugal, writes to the king to inform him of the elephant's death and states "that the inhabitants of Vienna will never forget [the elephant], for he had saved the life of a child on the very day he arrived in [Vienna]."
For Saramago, the measure of a life's journey is how well we "master the art of living" --- a phrase to be sure for which there will be more disagreements than agreements on the appropriate metric for this measure. In an entry in The Notebook (see September 28, 2010 post), Saramago writes about the Italian journalist Robert Saviano, who received death threats for having written a book denouncing the Camorra, a criminal organization. He says, "I think of Roberto Saviano whose head they would have on a plate, and I wonder whether one day we will wake up from the nightmare that is life for some many people, persecuted for telling the truth, the whole truth, and nothing but the truth. I feel humble, almost insignificant, faced with the dignity and courage of the writer and journalist Roberto Saviano, the man who has mastered the art of living."
Just a few nuggets from The Elephant's Journey worth quoting, and they connect to a theme about human creativity and storytelling that is reflected in previous posts, including the most recent post.
"It's hard to understand just why the archduke maximilian should have decided to make such a journey at this time of year, but that is how it's set down in history, as an incontrovertible, documented fact, supported by historians and confirmed by the novelist, who must be forgiven for taking certain liberties with names, not only because it is his right to invent, but also because he had to fill in certain gaps so that the sacred coherence of the story was not lost. It must be said that history is always selective, and discriminatory too, selecting from life only what society deems to be historical and scorning the rest, which is precisely where me might find the true explanation of facts, of things, of wretched reality itself. In truth, I say to you, it is better to be a novelist, a fiction writer, a liar." And thus is historical fiction. The Bible stories too --- the work of redactors, editors, and novelists, who must be forgiven for taking certain liberties because it was their right to invent and fill in certain gaps so that the sacred coherence of the story was not lost."
And finally, "People say a lot of things, and not all of them are true, but that is what human beings are like, they can as easily believe that the hair of an elephant, marinated in a little oil, can cure baldness, as imagine that they carry within them the one solitary light that will lead them along life's paths, even through mountain passes." Saramago, a master storyteller, knows that stories that defy human experience are not all true, like the conversation about Subhro's story about a cow that battles a pack of wolves told at that point in The Elephant's Journey, when the Portuguese are preparing to hand over their king's gift of the elephant to the Austrians. "[W]ho told you the story [about the cow and the wolves]? A Galician. And where did he hear it? He must have heard it from someone else, Or read it. As far as I know, he can't read. All right, perhaps he heard it and memorized it. Possibly, but I was simply interested in retelling it as best I could. You have an excellent memory, and the language in which you told the story was far from ordinary. Thank you, said Subhro, but now I would like to know which bits of the story remain unclear to you and failed to ring true? The first is that we are given to understand or, rather, it is explicitly stated that the struggle between the cow and the wolves lasted twelve days and twelve night, which would mean that wolves attacked the cow on the very first night and only withdrew on the twelfth, presumably having sustained some losses. We weren't there to see what happened. No, but anyone who knows anything about wolves would know that, although they live in a pack, they hunt alone. What are you getting at? asked Subhro. I'm saying that the cow wouldn't have been able to withstand a concerted attack by three or four wolves for one hour, let alone twelve days. So the whole story of the battling cow is a lie. No, the lie consists only in the exaggerations, linguistic affectations and half-truths that try to pass themselves off as whole-truths." Here, Saramago does not necessarily equate the novelist, the fiction writer, and the liar --- unless the novelist tries to pass his story off as "whole-truths." Tough words for some believers. But Saramago, as evidenced by the reaction to his The Gospel According to Jesus Christ, understood this.
The Elephant's Journey, Saramago's final novel, published two years before he died in 2010, is not as philosophically deep as his earlier novels, but this story of an elephant's journey from India to Lisbon to Vienna during the 16th century --- a historical event fictionalized by Saramago, because there is no detailed record of the journey that has been left behind --- ends in the death of the elephant two years after his arrival in Vienna. For Saramago, however, the elephant's death merely affirms life and our memory of life: the Austrian Archduke Maximilian, who received the elephant as a gift from King Joao III of Portugal, writes to the king to inform him of the elephant's death and states "that the inhabitants of Vienna will never forget [the elephant], for he had saved the life of a child on the very day he arrived in [Vienna]."
For Saramago, the measure of a life's journey is how well we "master the art of living" --- a phrase to be sure for which there will be more disagreements than agreements on the appropriate metric for this measure. In an entry in The Notebook (see September 28, 2010 post), Saramago writes about the Italian journalist Robert Saviano, who received death threats for having written a book denouncing the Camorra, a criminal organization. He says, "I think of Roberto Saviano whose head they would have on a plate, and I wonder whether one day we will wake up from the nightmare that is life for some many people, persecuted for telling the truth, the whole truth, and nothing but the truth. I feel humble, almost insignificant, faced with the dignity and courage of the writer and journalist Roberto Saviano, the man who has mastered the art of living."
Just a few nuggets from The Elephant's Journey worth quoting, and they connect to a theme about human creativity and storytelling that is reflected in previous posts, including the most recent post.
"It's hard to understand just why the archduke maximilian should have decided to make such a journey at this time of year, but that is how it's set down in history, as an incontrovertible, documented fact, supported by historians and confirmed by the novelist, who must be forgiven for taking certain liberties with names, not only because it is his right to invent, but also because he had to fill in certain gaps so that the sacred coherence of the story was not lost. It must be said that history is always selective, and discriminatory too, selecting from life only what society deems to be historical and scorning the rest, which is precisely where me might find the true explanation of facts, of things, of wretched reality itself. In truth, I say to you, it is better to be a novelist, a fiction writer, a liar." And thus is historical fiction. The Bible stories too --- the work of redactors, editors, and novelists, who must be forgiven for taking certain liberties because it was their right to invent and fill in certain gaps so that the sacred coherence of the story was not lost."
And finally, "People say a lot of things, and not all of them are true, but that is what human beings are like, they can as easily believe that the hair of an elephant, marinated in a little oil, can cure baldness, as imagine that they carry within them the one solitary light that will lead them along life's paths, even through mountain passes." Saramago, a master storyteller, knows that stories that defy human experience are not all true, like the conversation about Subhro's story about a cow that battles a pack of wolves told at that point in The Elephant's Journey, when the Portuguese are preparing to hand over their king's gift of the elephant to the Austrians. "[W]ho told you the story [about the cow and the wolves]? A Galician. And where did he hear it? He must have heard it from someone else, Or read it. As far as I know, he can't read. All right, perhaps he heard it and memorized it. Possibly, but I was simply interested in retelling it as best I could. You have an excellent memory, and the language in which you told the story was far from ordinary. Thank you, said Subhro, but now I would like to know which bits of the story remain unclear to you and failed to ring true? The first is that we are given to understand or, rather, it is explicitly stated that the struggle between the cow and the wolves lasted twelve days and twelve night, which would mean that wolves attacked the cow on the very first night and only withdrew on the twelfth, presumably having sustained some losses. We weren't there to see what happened. No, but anyone who knows anything about wolves would know that, although they live in a pack, they hunt alone. What are you getting at? asked Subhro. I'm saying that the cow wouldn't have been able to withstand a concerted attack by three or four wolves for one hour, let alone twelve days. So the whole story of the battling cow is a lie. No, the lie consists only in the exaggerations, linguistic affectations and half-truths that try to pass themselves off as whole-truths." Here, Saramago does not necessarily equate the novelist, the fiction writer, and the liar --- unless the novelist tries to pass his story off as "whole-truths." Tough words for some believers. But Saramago, as evidenced by the reaction to his The Gospel According to Jesus Christ, understood this.
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