Bernard Mandeville (January 31 post) and Henri Boulainvilliers may not have known of each other, but they were contemporaries, separated by the English Channel, during the era of the War of Spanish Succession and it is possible to loosely connect them with this War. Mandeville's idea that there is Virtue (public benefit) in Vice (war) was employed to justify England's participation in the War of Succession because of the benefit to the English economy. Boulainvilliers was obsessed with and conflicted by the idea of hereditary succession in France, and 300 years later we know this because of a series of pamphlets he wrote for the possible successors to Louis XIV.
Historian Harold Ellis' account of Boulainvilliers as an advisor to the Duke of Burgundy and later the Duke of Orleans (regent to Louis XV) unveils an intellectual crack in the ancien regime, decades before the French Revolution that toppled the French Monarchy. Boulainvilliers was part of a public discussion between representatives of the subgroups of the Second Estate (the aristocrats who inherited their titles, the peerage who owed their titles to the monarch, and others of noble heritage (such as Boulainvilliers) who were property owners) about their role in political decision-making. This was not a democratic movement as we think of it today or even as contemplated by the American Constitution later in the 18th century; yet it was incipient republicanism, which even the royal recipients of Boulainvilliers' essays seemed to understand because Boulainvilliers' failed in his efforts to persuade the regent, Orleans, to accept his idea that the Second Estate ought to have a voice in deciding of who succeeds a dying monarch who leaves no direct heirs. Succession was the limited issue for this incipient republicanism; no one was advocating the overthrow of the French monarchy and Boulainvilliers limited his criticism of a monarchy to the concept of "absolute" or decadent monarchy. The most interesting aspect of this history to me is that the discussion was even happening at all, beginning while the Sun King was still alive.
Yet this was the Enlightenment. Boulainvilliers is also responsible for spreading Spinoza's ideas in France, and he wrote a treatise on Spinoza's Theologico-Political Treatise , which was a defense of secular government and religious tolerance that was not well-received by the European ruling class. Among Spinoza's "radical" ideas are the seeds of democratic institutions, freedom of speech and religious toleration, freedoms that only six decades after Boulainvilliers' death found expression in the United States Constitution. And while Boulainvilliers is not espousing radical ideas in the Spinozan sense, the discussion within the Second Estate of which Boulainvilliers was a part is that same expression of freedom in its incipiency.
Boulainvilliers, as with others who were part of this discussion, turned to French history to identify the source of the royal authority and its legitimacy, and Boulainvilliers' survey of French history back to the Frankish conquest of Gaul led him to conclude that the authority of the monarchy is derived from the "nation." The nation does not include serfs or others of the Third Estate who were later responsible for overthrowing the French monarchy, but it did include The Second Estate, and the discussion revolved around which members of the Second Estate: just the royal aristocracy? the peerage? Or as Boulainvilliers advocated --- members of the Estates-General, even other propertied nobles such as himself?
As revealed by Ellis, Boulainvilliers was intellectually conflicted. Boulainvilliers appears at times to be hostile to hereditary titles, yet his adult intellectual life is devoted to and in defense of royals who solicited his histories and opinions. He was openly hostile to "absolute" monarchy, but did not challenge the Bourbon monarchy. Central to Boulainvilliers' thought, however conflicted he might have been, is the idea of a meritocracy. He appears greatly bothered that persons who were in positions of responsibility --- either because they inherited that position or they were awarded it by the King --- were not qualified to hold those positions. Apparently he believed that his patron, the regent -- Duke of Orleans -- was qualified, and Boulainvilliers was greatly disappointed that Orleans did not seize the opportunity to turn the monarchy in only a slightly more liberal direction.