Marie Jean Antoine Nicolas Caritat, marquis de Condorcet
(September 17, 1743 - March 28, 1794)

French philosopher, mathematician, social scientist, economist, gentleman, politician and humanitarian, the Marquis of Condorcet was the only giant of the Enlightenment present at the revolution.
Born in Saint-Quentin and educated atNavarre, Condorcet arrived in Paris in 1762.  In 1765, Condorcet published his first work on mathematics.  In 1769, he was elected to the prestigiousAcadémie française.  From 1773, he was appointed perpetual secretary of the Académie.   Condorcet fell in with the clique of Voltaire, Diderot and, above all, Jacques Turgot, who would serve as his mentor until his death.  Turgot encouraged him to explore economic questions.Like many other Enlightenment thinkers, Hismathematique sociale drew upon Enlightenment rationalism to explain socio-economic phenomona by mathematical (or, more commonly, statistical) methods.  He distanced himself from Rousseau's attempt to alter classic rationalism with sentiment, preferring instead to raise reason to the mathematical level.  Thus, Condorcet argued that the only social obligation is to obey the generalreason, rather than the generalwill.  In this way, the will of the majority is automatically trumped if it fails to comply with reason. 
Condorcet was an optimist on social progress, believing in the ultimate perfectability" of man.  Malthus's population doctrines were partly directed against his ideas. Condorcet's research programme was abandoned wholesale after the French Revolution - particularly after J.B. Say's efforts to redirect French theory towards non-mathematical British political economy. A good friend of Jacques Turgot, Condorcet was appointed by Turgot as master of the mint in 1774.  He resigned in protest in 1776 over Turgot's dismissal, but went on to serve until 1791 (writing, in the meantime, an expository biography of Turgot and his famous 1785 Condorcet Paradox on the intransitivity of majority preference).Condorcet took a leading role in the 1789 French Revolution, which he saw as embodying a great hope for his "rationalist" reconstruction of society.  However, he voted against the execution of the Louis XVI and opposed the arrest of the Girodins.  As a result of these principled moves, Condorcet was denounced as a traitor by the Jacobins and went into hiding in 1791.  It was during this period that he wrote his great humanitarian tract on the progress of the human spirit (1795).   Finally captured in 1794, he reportedly took his own life in prison, although the possibility that he was murdered cannot be ruled out.

Taken from:

http://cepa.newschool.edu/het/profiles/condorcet.htmAlso see:
http://www.ecn.bris.ac.uk/het/condorcet/new/Condorcet01.html#ancre358425
http://www-groups.dcs.st-and.ac.uk/%7Ehistory/Mathematicians/Condorcet.html]
http://5.1911encyclopedia.org/C/CO/CONDORCET.htm
http://en.wikipedia.org/wiki/Marquis_de_Condorcet