1596-1650 1632-1704 17thcentury 194 ancient atomictheory b1887 biography contingency(philosophy) contributionsinmechanicalphilosophydescartes contributionsinmechanicalphilosophygassendi descartes france freewillanddeterminism gassendi god historiography history historyofdoctrines john knowledge locke necessity(philosophy) philosophers philosophy philosophyofnature pierre providenceandgovernmentofgod rené science theoryof will