Philo of Megara

Greek philosopher

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

July 1, 2026

Quick Summary

Philo of Megara was a Greek philosopher and a student of Socrates who founded the Megarian school of philosophy in the 4th century BCE. The Megarian school was known for its logical puzzles and its influence on Stoic logic. Philo, along with other Megarians like Diodorus Cronus, debated interpretations of conditional propositions and explored logical paradoxes. While the school's positive doctrines were less emphasized, their dialectical skills and focus on logic were significant. Philo's interpretation of conditional propositions, where a conditional is true if it does not have a true antecedent and a false consequent at the present time, is known as material implication.1234

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

6 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

history of logic
The Megarians and the Stoics
…century bce) and his pupil Philo of Megara. The Stoics were followers of Zeno of Citium (c. 336–c. 265 bce). By far the most important Stoic logician was Chrysippus (c. 279–206 bce). The influence of Megarian on Stoic logic is indisputable, but many details are uncertain, since all but fragments…
Read More
…century bce) and his pupil Philo of Megara. The Stoics were followers of Zeno of Citium (c. 336–c. 265 bce). By far the most important Stoic logician was Chrysippus (c. 279–206 bce). The influence of Megarian on Stoic logic is indisputable, but many details are uncertain, since all but fragments…
Read More