His astronomy seems surprisingly crude for one who stood in close relations with the Pythagoreans. We are told that he adopted Anaximenes’ theory of the sun and Herakleitos’s explanation of eclipses.[494] It is all the more remarkable that he is credited with originating the idea, which it required all Plato’s authority to get accepted later, that the planets have an orbital motion in the opposite direction to the diurnal revolution of the heavens.[495] This, if true, probably stood in close connexion with his saying that soul was immortal because it resembled immortal things, and was always in motion like the heavenly bodies.[496] He seems, in fact, to be the real author of the curious view which Plato put into the mouth of the Pythagorean Timaios, that the soul has circles revolving just as the heavens and the planets do. This too seems to be the explanation of his further statement that man dies because he cannot join the beginning to the end.[497] The orbits of the heavenly bodies always come full circle, but the circles in the head may fail to complete themselves. This new version of the parallelism between the microcosm and the macrocosm would be perfectly natural for Alkmaion, though it is, of course, no more than a playful fancy to Plato. Footnote 494: Aet. ii. 22, 4, πλατὺν εἶναι τὸν ἥλιον; 29, 3, κατὰ τὴν τοῦ σκαφοειδοῦς στροφὴν καὶ τὰς περικλίσεις (ἐκλείπειν τὴν σελήνην). Footnote 495: Aet. ii. 16, 2, (τῶν μαθηματικῶν τινες) τοὺς πλανήτας τοῖς ἀπλάνεσιν ἀπὸ δυσμῶν ἐπ’ ἀνατολὰς ἀντιφέρεσθαι. τούτῳ δὲ συνομολογεῖ καὶ Ἀλκμαίων. Footnote 496: Arist. _de An._ Α, 2. 405 a 30 (R. P. 66 c). Footnote 497: Arist. _Probl._ 17, 3. 916 a 33, τοὺς ἀνθρώπους φησὶν Ἀλκμαίων διὰ τοῦτο ἀπόλλυσθαι, ὅτι οὐ δύνανται τὴν ἀρχὴν τῷ τέλει προσάψαι. Alkmaion’s theory of health as “isonomy” is at once that which most clearly connects him with earlier inquirers like Anaximander, and also that which had the greatest influence on the subsequent development of philosophy. He observed, to begin with, that “most things human were two,” and by this he meant that man was made up of the hot and the cold, the moist and the dry, and the rest of the opposites.[498] Disease was just the “monarchy” of any one of these—the same thing that Anaximander had called “injustice”—while health was the establishment in the body of a free government with equal laws.[499] This was the leading doctrine of the Sicilian school of medicine which came into existence not long after, and we shall have to consider in the sequel its influence on the development of Pythagoreanism. Taken along with the theory of “pores,”[500] it is of the greatest importance for later science. Footnote 498: Arist. _Met._ Α, 5. 986 a 27 (R. P. 66). Footnote 499: