Born in 1652. Went to Paris at 23 to work as an arithmetical expert, published an eponymous theorem in 1961. Tangent lines were never the same again.*

*Actually they were, he just proved something that was apparent to the naked eye.†

†I may or may not have a bad attitude toward real analysis at this point.‡

‡I totally have a bad attitude.§

§Footnotes Forever!