Search Result for "heraclitus": 
Wordnet 3.0

NOUN (1)

1. a presocratic Greek philosopher who said that fire is the origin of all things and that permanence is an illusion as all things are in perpetual flux (circa 500 BC); 



WordNet (r) 3.0 (2006):

Heraclitus
    n 1: a presocratic Greek philosopher who said that fire is the
         origin of all things and that permanence is an illusion as
         all things are in perpetual flux (circa 500 BC)