Page:Early Greek philosophy by John Burnet, 3rd edition, 1920.djvu/208

194 The quotation unfortunately ends in this abrupt way, but we learn two things from it. In the first place, Alkmaion possessed that reserve which marks all the best Greek medical writers; and in the second place, he dedicated his work to the heads of the Pythagorean Society.

Alkmaion's importance really lies in the fact that he is the founder of empirical psychology. He regarded the brain as the common sensorium, a view which Hippokrates and Plato adopted from him, though Empedokles, Aristotle, and the Stoics reverted to the more primitive view that the heart is the central organ of sense. There is no reason to doubt that he made this discovery by anatomical means. We have authority for saying that he practised dissection, and, though the nerves were not yet recognised as such, it was known that there were certain "passages" (πόροι) which might be prevented from communicating sensations to the brain by lesions. He also distinguished between sensation and understanding, though we have no means of knowing where he drew the line between them. His theories of the special senses are of great interest. We find in him already, what is characteristic of Greek theories of vision as a whole, the attempt to combine the view of vision as a radiation proceeding from the eye with that which attributes it to an image reflected in the eye. He knew the importance of air for the sense of hearing, though he called it the void, a thoroughly Pythagorean touch. With regard to the other senses, our information is more