Aristotle, Nicomachean Ethics
H. Rackham, Ed.

good and pleasant in itself, for it is definite, and definiteness is a part of the essence of goodness, and what is essentially good is good for the good man, and hence appears to be pleasant to all men. [8] We must not argue from a vicious and corrupt life, or one that is painful, for such a life is indefinite, like its attributes.¹ （The point as to pain will be clearer in the sequel.²） [9] But if life itself is good and pleasant （as it appears to be, because all men desire it, and virtuous and supremely happy men most of all, since their way of life is most desirable and their existence the most blissful） ; and if one who sees is conscious³ that he sees, one who hears that he hears, one who walks that he walks, and similarly for all the other human activities there is a faculty that is conscious of their exercise, so that whenever we perceive, we are conscious that we perceive, and whenever we think, we are conscious that we think, and to be conscious that we are perceiving or thinking is to be conscious that we exist （for existence, as we saw, is sense-perception or thought）;