Zeno of Citium, in Cyprus, died in c. 264 B.C. and was probably born in 336. Citium was a Greek colony in Cyprus. Zeno's ancestry was probably not entirely Greek. He may have had Semitic, perhaps Phoenician, ancestors.
Diogenes Laertius provides biographical details and quotations from the Stoic philosopher. He says Zeno was the son of Innaseas or Demeas, and a pupil of Crates. He arrived at Athens at about the age of 30. He wrote treatises on the Republic, life according to nature, the nature of man, appetite, becoming, law, passions, Greek education, sight, and many more. He left the cynic philosopher Crates, took up with Stilpon and Xenocrates, and developed his own following. Epicurus called Zeno's followers Zenonians, but they became known as Stoics because he delivered his discourses while walking in a colonnade -- stoa, in Greek. The Athenians honored Zeno with a crown, statue, and the city keys.
Zeno of Citium is the philosopher who said that the definition of a friend was "another I."
"This is the reason why we have two ears and only one mouth, that we may hear more and speak less."
Quoted by Diogenes Laërtius, vii. 23.