Megarian school of philosophy

The Megarian school of philosophy, which flourished in the 4th century BC, was founded by Euclides of Megara, one of the pupils of Socrates. Its ethical teachings were derived from Socrates, recognizing a single good, which was apparently combined with the Eleatic doctrine of Unity. Some of Euclides' successors developed logic to such an extent that they became a separate school, known as the Dialectical school. Their work on modal logic, logical conditionals, and propositional logic played an important role in the development of logic in antiquity.

The Megarian school of philosophy was founded by Euclides of Megara, who had been one of the pupils of Socrates in the late 5th century BC. His successors, as head of the school in Megara, were said to have been Ichthyas (mid 4th century BC), and Stilpo (late 4th century BC). It is unlikely, however, that the Megarian school was a genuine institution, nor did it have a unified philosophical position. It was said that the philosophers of the school were first called Megarians and that later they were called Eristics, and then Dialecticians, but it is probable that these names designated splinter groups distinct from the Megarian school. Besides Ichthyas, Euclides' most important pupils were Eubulides of Miletus and Clinomachus of Thurii. It seems to have been under Clinomachus that a separate Dialectical school was founded, which placed great emphasis on logic and dialectic, and Clinomachus was said to have been "the first to write about propositions and predicates." However, Euclides himself taught logic, and his pupil, Eubulides, who was famous for employing celebrated paradoxes, was the teacher of several later dialecticians.

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