Newton's infinitesimal calculus

de bene esse: literally, of well-being, morally acceptable but subject to future validation or exception 

Newton received his BA degree from Trinity in January 1665 as the bubonic plague was casting it's dark shadow across the country.

Cambridge University closed down on August 7, 1665. In that short break, Newton began work on inventing a branch of mathematics called infinitesimal calculus. By 1687, he had fully developed his theories and introducing them to his students at Cambridge. These were the first students to feel the wrath of infinitesimal calculus.