|A comparative distribution of numbers of French geniuses from James Cattell’s 1894 Cattell 1000 rankings. |
In 1592, when the complete works of Michel Montaigne became available, particularly his "Essays", this became an early anchor-point for the growth of later French geniuses.
In 1729, when three copies of Jean Meslier’s The Testament were found under his bed, these worked to grow French philosophical atheism, inspiring, those including: Baron d’Holbach, Denis Diderot, and Voltaire (Ѻ).
In 1794, when the Ecole Polytechnique was founded, this became a hotbed for French scientific genius and engineering.
The following are related quotes:
“Montaigne was the first Frenchman who dared to think.”— Julien la Mettrie (1751), “Anti-Seneca” (pg. 129)
“The result was that between 1790 and 1825, France produced the brightest galaxy of scientific genius that the world has witnessed to day.”— Donald Cardwell (1971), From Watt to Clausius (pgs. 119-20) 
1. Cardwell, Donald S.L. (1971). From Watt to Clausius: the Rise of Thermodynamics in the Early Industrial Age (pgs. 119-20). Cornell University Press.
2. Cattell, James, M. (1894). “A Statistical Study of Eminent Men”, statistics of paper presented to the American Psychological Association Dec.; abstract published in the Psychological Review, Mar., 1895; read in present form as a lecture before the Philosophical Club of Yale University, 1897; Popular Science Monthly (1903), 62: 359-77.