Book x

. In this way, too, we get a historical development of the theory of pleasure: Plato and Speusippus said it is generation (cf. Plato's _Philebus_): Aristotle said it is psychical

## activity sometimes requiring bodily generation, sometimes not (E.N.

vii. = E.E. [zeta]): Aristotle, or some Aristotelian, afterwards said that it is a supervening end completing an activity (E.N. x.). Secondly, some modern commentators, starting from the false conclusion that the definition of pleasure as activity (E.N. vii. = E.E. [zeta]) is by Eudemus, and supposing without proof that he was also author of the first three books of the _Eudemian Ethics_, have further asserted that these are a better introduction than the first four books of the _Nicomachean Ethics_ to the books common to both treatises (E.N. Books v.-vii.= E.E. Books [Delta]-[Zeta]), and have concluded that Eudemus wrote these common books. But we have seen that Aristotle wrote the first three books of the _Eudemian_ as an earlier draft of the _Nicomachean Ethics_; so that, even so far as they form a better introduction, this will not prove the common books to be by Eudemus. Again, those first three books are a better introduction only in details; whereas in regard to the all-important subject of prudence as distinct from wisdom, they are so bad an introduction that the common book which discusses that subject at large (E.N.