Alcmaeon of Croton

Alcmaeon of Croton (in Magna Graecia) (/ælkˈmiːən/; Greek: Ἀλκμαίων ὁ Κροτωνιάτης, Alkmaiōn, gen.: Ἀλκμαίωνος; 5th century BCE) was one of the most eminent natural philosophers and medical theorists of antiquity. His father's name was Peirithus (Peirithos). He is said by some to have been a pupil of Pythagoras, and he is believed to have been born c. 510 BCE. Although he wrote primarily about medical topics, there is some suggestion that he was a philosopher of science, not a physician. He also practiced astrology and meteorology. Nothing more is known of the events of his life.

He was considered by many an early pioneer and advocate of anatomical dissection and was said to be the first to identify Eustachian tubes. His celebrated discoveries in the field of dissection were noted in antiquity, but whether his knowledge in this branch of science was derived from the dissection of animals or of human bodies is disputed.Calcidius, on whose authority the fact rests, merely says "qui primus exsectionem aggredi est ausus," and the word exsectio would apply equally well in either case; some modern scholars doubt Calcidius' word entirely.

He also was the first to dwell on the internal causes of illnesses. It was he who first suggested that health was a state of equilibrium between opposing humors and that illnesses were because of problems in environment, nutrition and lifestyle. He is said also to have been the first person who wrote on natural philosophy (φυσικὸν λόγον), and to have invented fables. He also wrote several other medical and philosophical works, of which nothing but the titles and a few fragments have been preserved by Stobaeus,Plutarch, and Galen. His Concerning Nature might be the earliest example of Greek medical literature.

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