Nicomachean Ethics

designates. For since our soul was brought forth by its creator with such capacity that it can receive the knowledge of all beings (on account of which the ancient philosophers called it the place of forms), a certain habit must deservedly be given by which the human soul can perceive all things that exist. For it is necessary that knowledge be equated to the known, as the measure to the measured, and number to the numbered; whence the ancients said that the science of the thing which is known is a certain measure. Since, however, philosophy appears to be such a habit, by which our soul can perceive the things that exist, it is not undeservedly said by Plato, on the part of the subject, to be the knowledge of those things which exist. Moreover, the second definition of philosophy on the part of the subject, which Plato provided, shows that philosophy is the perception of divine and human things. For of those things which exist, some are said to fall under the category of cause, others of effect, and some are called divine, others human, the perception of all of which is called philosophy by Plato. Therefore, philosophy is described and defined by these two accounts from the subject with which it is concerned. The third definition of Plato is taken on the part of the end, by which he says that philosophy is the likeness by which man becomes similar to God as far as is possible. For it seems ridiculous to think that while there is some end for even base habits—over which philosophy appears to be superior in no small degree—one should posit no end for philosophy itself, but consider so noble and so excellent a habit to be in vain. The end of philosophy, therefore, is that through it man may know the highest good and God himself, and that by contemplating and acting, all other things being set aside, he may become similar to him as far as is possible. We do not, however, say that man becomes similar to God in substance, nor in nature, nor in other divine conditions by any means, but by a likeness of operations. Truly, likeness does not prove identity of essence. Man, therefore, becomes similar to God in two ways, that is, either by acting or by contemplating according to