Mathematician and author, the Marquis de Condorcet (1743-1794) was an aristocrat who nevertheless embraced the early stage of the French Revolution. Even as the Jacobins hunted him down during the Reign of Terror—he was a moderate and opposed putting King Louis XVI to death—he wrote the Sketch for a Historical Picture of the Progress of the Human Mind, expressing his faith in a future guided by science and reason. Two days after his arrest, he killed himself in prison rather than face execution.
Condorcet’s ideals live on, however, in the way most of the world measures things: the metric system. He believed a universal and standard system would allow people to calculate their own best interests, “without which they cannot be really equal in rights . . . nor really free.”
At the time of the French Revolution in 1789, Paris was the global capital of science, whose leading lights, the savants (wise ones), made lasting contributions to physics, chemistry, and biology. (A century earlier, France was also the dueling capital of Europe.)