Epicurus
Epicurus (, EH-pih-KURE-əs; Ancient Greek: Ἐπίκουρος Epikouros; 341–270 BC) was an ancient Greek philosopher who founded Epicureanism, a highly influential school of philosophy that asserted that philosophy's purpose is to attain as well as to help others attain tranquil lives, characterized by freedom from fear and the absence of pain.
Epicurus advocated that people were best able to pursue philosophy by living a self-sufficient life surrounded by friends; he and his followers were known for eating simple meals and discussing a wide range of philosophical subjects at "the Garden", the school he established in Athens. Epicurus taught that although the gods exist, they have no involvement in human affairs. Like the earlier philosopher Democritus, Epicurus claimed that all occurrences in the natural world are ultimately the result of tiny, invisible particles known as atoms moving and interacting in empty space, though Epicurus also deviated from Democritus by proposing the idea of atomic "swerve", which holds that atoms may deviate from their expected course, thus permitting humans to possess free will in an otherwise deterministic universe.
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Definition from Wikipedia – Epicurus