What was the year of birth of the mathematician that is credited with developing infinitesimal calculus and using Jean Picard's measurement of earth to create his theory of universal gravitation?
Jean Picard:  Isaac Newton was to use this value in his theory of universal gravitation. Isaac Newton: Sir Isaac Newton {'1': ", '2': ", '3': ", '4': "} ( ; 25 December 1642 – 20 March 1726/27) was an English mathematician, astronomer, and physicist (described in his own day as a "natural philosopher") who is widely recognised as one of the most influential scientists of all time and a key figure in the scientific revolution. Isaac Newton:  Newton also made pathbreaking contributions to optics, and he shares credit with Gottfried Wilhelm Leibniz for developing the infinitesimal calculus.
1642