Chapter 8 — Arguments whereby it seems to be proved that evil is a nature or a thing

It would seem that certain arguments militate against the aforesaid statement.

For each thing derives its species from its proper difference. Now evil is a specific difference in certain genera (namely, in moral habits and acts), because as virtue is a good habit according to its species, so the contrary vice is an evil habit according to its species, and the same applies to virtuous and vicious acts. Therefore, evil gives certain things their species. Therefore, it is an essence, and is natural to certain things.

Further. Each of two contraries is a nature: for if it predicated nothing, one of the contraries would be a pure privation or negation. But good and evil are stated to be contraries. Therefore, evil is a nature.

Again. Aristotle in his Predicaments says that good and evil are the genera of contraries. (Aristotle, Categories, ch. 8 [27].) Now every genus has an essence or nature: for there are no species or differences of non-being, so that what is not cannot be a genus. Therefore, evil is an essence and a nature.

Also. Whatever is active is a thing. Now evil as such is active: for it counteracts and corrupts good. Therefore, evil as such is a thing.

Moreover. Whatever can be more or less must be a thing admitting of degrees, since negations and privations do not admit of being more or less. Now among evils we find one to be worse than another. Therefore, it seems that evil must be a thing.

Furthermore. ‘Thing’ and ‘being’ are convertible terms. Now evil exists in the world. Therefore, it is a thing and a nature.