Aristotle

Aristotle
Aristotle was a Greek philosopher and scientist born in the city of Stagira, Chalkidice, on the northern periphery of Classical Greece. His father, Nicomachus, died when Aristotle was a child, whereafter Proxenus of Atarneus became his guardian. At eighteen, he joined Plato's Academy in Athens and remained there until the age of thirty-seven. His writings cover many subjects – including physics, biology, zoology, metaphysics, logic, ethics, aesthetics, poetry, theater, music, rhetoric, linguistics, politics and government – and constitute the first comprehensive system...
NationalityGreek
ProfessionPhilosopher
That in the soul which is called mind (by mind I mean that whereby the soul thinks and judges) is, before it thinks, not actually any real thing. For this reason it cannot reasonably be regarded as blended with the body
Opinion involves belief (for without belief in what we opine we cannot have an opinion), and in the brutes though we often find imagination we never find belief.
Thinking is different from perceiving and is held to be in part imagination, in part judgment
There are two distinctive peculiarities by reference to which we characterize the soul (1) local movement and (2) thinking, discriminating, and perceiving. Thinking both speculative and practical is regarded as akin to a form of perceiving; for in the one as well as the other the soul discriminates and is cognizant of something which is.
All food must be capable of being digested, and that what produces digestion is warmth; that is why everything that has soul in it possesses warmth.
The soul is the cause or source of the living body. The terms cause and source have many senses. But the soul is the cause of its body alike in all three senses which we explicitly recognize. It is (a) the source or origin of movement, it is (b) the end, it is (c) the essence of the whole living body.
But nothing is yet clear on the subject of the intellect and the contemplative faculty. However, it seems to be another kind of soul, and this alone admits of being separated, as that which is eternal from that which is perishable, while it is clear from these remarks that the other parts of the soul are not separable, as some assert them to be, though it is obvious that they are conceptually distinct.
We have no evidence as yet about mind or the power to think; it seems to be a widely different kind of soul, differing as what is eternal from what is perishable; it alone is capable of existence in isolation from all other psychic powers.
The ensouled is distinguished from the unsouled by its being alive. Now since being alive is spoken of in many ways, even if only one of these is present, we say that the thing is alive, if, for instance, there is intellect or perception or spatial movement and rest or indeed movement connected with nourishment and growth and decay. It is for this reason that all the plants are also held to be alive . . .
What has soul in it differs from what has not, in that the former displays life. Now this word has more than one sense, and provided any one alone of these is found in a thing we say that thing is living. Living, that is, may mean thinking or perception or local movement and rest, or movement in the sense of nutrition, decay and growth. Hence we think of plants also as living, for they are observed to possess in themselves an originative power through which they increase or decrease in all spatial directions;
Two characteristic marks have above all others been recognized as distinguishing that which has soul in it from that which has not - movement and sensation.
The knowledge of the soul admittedly contributes greatly to the advance of truth in general, and, above all, to our understanding of Nature, for the soul is in some sense the principle of animal life.
Some persons hold that, while it is proper for the lawgiver to encourage and exhort men to virtue on moral grounds, in the expectation that those who have had a virtuous moral upbringing will respond, yet he is bound to impose chastisement and penalties on the disobedient and ill-conditioned, and to banish the incorrigible out of the state altogether. For (they argue) although the virtuous man, who guides his life by moral ideals, will be obedient to reason, the base, whose desires are fixed on pleasure, must be chastised by pain, like a beast of burden.
As to adultery, let it be held disgraceful, in general, for any man or woman to be found in any way unfaithful when they are married, and called husband and wife. If during the time of bearing children anything of the sort occur, let the guilty person be punished with a loss of privileges in proportion to the offense.