The Society for Ancient Greek Philosophy Newsletter

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The first part of the paper explores Aristotle's biological concept of an eidos (species or form) in comparison with modern biological taxonomy. The second part outlines normative determinants of an Aristotelian eidos. The third part considers two passages in which Aristotle compares non-biological eide to biological: pleasures, in EN 10.4-5, and kinds of government in Pol. 4.4.


Anthony Preus presented “Eidos as Norm in Aristotle’s Biology” to the Society for Ancient Greek Philosophy at its meeting with the Eastern Division of the American Philosophical Association in Washington DC in 1977. It was published in Nature and System I (1979) 79-101 and reprinted in J. P. Anton & A. Preus, eds. 1983. Essays in Ancient Greek Philosophy, vol. 2. SUNY, 340-363.

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