Alcmaeon in Harpers Dictionary of Classical Antiquities
（Ἀλκμαίων). A native of Argos and son of AmphiaraŁs (q.v.) and Eriphylť. As his father, in departing on the expedition of the Seven against Thebes, had bound him and his brother Amphilochus, then mere boys, to avenge him on their faithless mother, Alcmaeon refused to take part in the second expedition, that of the Epigoni (q.v.), till he had first fulfilled that filial duty; nevertheless his mother, bribed by Thersander with the garment of Harmonia, persuaded him to go. The real leader at the siege of Thebes, he slew the Theban king, Laodamas, and was the first to enter the conquered city. On returning home, he, at the bidding of the Delphian Apollo, avenged his father by slaying his mother, with, or according to some accounts, without, his brother's help; but immediately, like Orestes, he was set upon by the Furies, and wandered distracted, seeking purification and a new home. Phegeus, of the Arcadian Psophis, half purified him of his guilt, and gave him his daughter Arsinoe or Alphesiboea to wife, to whom he presented the jewels of Harmonia, which he had brought from Argos. But soon the crops failed in the land, and he fell into his distemper again, till, after many wanderings, he arrived at the mouth of the AcheloŁs, and there, in an island that had floated up, he found the country promised by the god, which had not existed at the time of his dying mother's curse, and so he was completely cured. He married AcheloŁs's daughter, Callirrhoe, by whom he had two sons, Acarnan and Amphoterus (q.v.). Unable to withstand his wife's entreaties that she might have Harmonia's necklace and robe, he went to Phegeus in Arcadia, and begged those treasures of him, pretending that he would dedicate them at Delphi for the perfect healing of his madness. He obtained them; but Phegeus, on learning the truth, set his son to waylay him on the road, and rob him of his treasure and his life. Alcmaeon 's sons then avenged their father's death on his murderers. Alcmaeon received divine honours after death, and had a sanctuary at Thebes and a consecrated tomb at Psophis.
Alcmaeon of Croton in Wikipedia
Alcmaeon (Gr. Ἀλκμαίων, Alkmaiōn, gen.: Ἀλκμαίωνος; 5th century BC) of Croton (in Magna Grścia) 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 may have been born around 510 BC. Although he wrote mostly on medical topics there is some suggestion that he was not a physician but a philosopher of science; he also indulged in 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 still a disputed question. 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.
Alcmaeon of Croton expiremented with live animals by cutting the nerve behind the eye to study vision. He also contributed to the study of medicine by establishing the connection between the brain and the sense organs, and outlined the paths of the optic nerves as well as stating that the brain is the organ of the mind. However, his theories were not without mistakes. He said that sleep occurs when blood vessels in the brain are filled and that waking is caused by the emptying of these vessels. He also stated that the eye contains both fire and water.
Although Alcmaeon is often called a pupil of Pythagoras, there is great reason to doubt whether he was a Pythagorean at all; his name seems to have crept into lists of Pythagoreans given us by later writers. Aristotle mentions him as nearly contemporary with Pythagoras, but distinguishes between the stoicheia (στοιχεῖα) of opposites, under which the Pythagoreans included all things; and the double principle of Alcmaeon, according to Aristotle, less extended, although he does not explain the precise difference. Other doctrines of Alcmaeon have been preserved to us. He said that the human soul was immortal and partook of the divine nature, because like the heavenly bodies it contained in itself a principle of motion. The eclipse of the moon, which was also eternal, he supposed to arise from its shape, which he said was like a boat. All his doctrines which have come down to us relate to physics or medicine; and seem to have arisen partly out of the speculations of the Ionian School, with which rather than the Pythagorean, Aristotle appears to connect Alcmaeon, partly from the traditional lore of the earliest medical science.