Diogenes the Cynic, also known as Diogenes of Sinope (c. 413/403–c. 324/321 BC), was an ancient Greek philosopher and one of the founders of Cynicism. Renowned for his ascetic lifestyle, biting wit, and radical critiques of social conventions, he became a legendary figure whose life and teachings have been recounted, often through anecdote, in both antiquity and later cultural traditions.