Virtue also depends on ourselves. And so also does vice. For where we are free to act we are also free to refrain from acting, and where we are able to say No we are also able to say Yes; if therefore we are responsible for doing a thing when to do it right, we are also responsible for not doing it when not to do it is wrong, and if we are responsible for rightly not doing a thing, we are also responsible for wrongly doing it.

Nature does nothing in vain.

for we are inquiring not in order to know what virtue is, but in order to become good, since otherwise our inquiry would have been of no use

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 . . .

The best way to teach morality is to make it a habit with children.

It is clear, then, that the earth must be at the centre and immovable, not only for the reasons already given, but also because heavy bodies forcibly thrown quite straight upward return to the point from which they started, even if they are thrown to an infinite distance. From these considerations then it is clear that the earth does not move and does not lie elsewhere than at the centre.

In bad or corrupted natures the body will often appear to rule over the soul, because they are in an evil and unnatural condition. At all events we may firstly observe in living creatures both a despotical and a constitutional rule; for the soul rules the body with a despotical rule, whereas the intellect rules the appetites with a constitutional and royal rule. And it is clear that the rule of the soul over the body, and of the mind and the rational element over the passionate, is natural and expedient; whereas the equality of the two or the rule of the inferior is always hurtful.