Pleasure is deserving of consideration, from its close intimacy with the constitution of our race; on which account, in our training of youth, we steer them by pleasure and pain; and it is of the first importance that they should feel pleasure in what they ought, and displeasure in what they ought, as the groundwork (or principium) of good ethical dispositions.  Such a topic can never be left unnoticed, especially when we look at the great difference of opinion thereupon.  Some affirm pleasure to be the chief good [Eudoxus].  Others call it altogether vile and worthless [party of Speusippus].  Of these last, some perhaps really think so; but the rest are actuated by the necessity of checking men’s too great proneness to it, and disparage it on that account.  This policy Aristotle strongly censures, and contends for the superior efficacy of truth (I.).

The arguments urged by Eudoxus as proving pleasure to be the chief good, are, (1) That all beings seek pleasure; (2) and avoid its opposite, pain; (3) that they seek pleasure as an end-in-itself, and not as a means to any farther end; (4) that pleasure, added to any other good, such as justice or temperance, increases the amount of good; which could not be the case, unless pleasure were itself good.  Yet this last argument (Aristotle urges) proves pleasure to be a good, but not to be the Good; indeed, Plato urged the same argument, to show that pleasure could not be The Good:  since The Good (the Chief Good) must be something that does not admit of being enhanced or made more good.  The objection of Speusippus,—­that irrational creatures are not to be admitted as witnesses,—­Aristotle disallows, seeing that rational and irrational agree on the point; and the thing that seems to all, must be true.  Another objection, That the opposite of pain is not pleasure, but a neutral state—­is set aside as contradicted by the fact of human desire and aversion, the two opposite states of feeling (II.).

The arguments of the Platonists, to prove that pleasure is not good, are next examined. (1) Pleasure, they say, is not a quality; but neither (replies Aristotle) are the exercises or actual manifestations of virtue or happiness. (2) Pleasure is not definite, but unlimited, or admitting of degrees, while The Good is a something definite, and does not admit of degrees.  But if these reasoners speak about the pure pleasures, they might take objection on similar grounds against virtue and justice also; for these too admit of degrees, and one man is more virtuous than another.  And if they speak of the mixed pleasures (alloyed with pain), their reasoning will not apply to the unmixed.  Good health is acknowledged to be a good, and to be a definite something; yet there are nevertheless some men more healthy, some less. (3) The Good is perfect or complete; but objectors urge that no motion or generation is complete, and pleasure is in one of these two categories.  This last assertion Aristotle