Aquinas - Whether evil is a nature

(Originally written April 17, 2007 in Book 25)

St. Thomas Aquinas
The Summa Theologica
Benzinger Brothers, edition, 1947

Treatise on the Distinction of Good and Evil

Concerning evil there are six points to be considered:
1. Whether evil is a nature?
2. Whether evil is found in things?
3. Whether good is the subject of evil?
4. Whether evil totally corrupts good?
5. The division of evil into pain and fault
6. Whether pain, or fault has more the nature of evil.

Whether evil is a nature?

Objections:

A) 1. Every genus is a nature
2. Evil is a genus
3. But Aristotle claims that good and evil are not in a genus, but are genera of other things
4. Therefore, evil is a nature.

B) 1. Every difference which constitutes a species is a nature
2. Evil is a difference constituting a species of morality
3. Therefore, evil signifies a nature

C) 1. Each extreme of two contraries is a nature
2. Evil and good are not opposed as privation and habit, but as contraries
3. Therefore, Evil signifies a nature

D) 1. What is not, acts not
2. Evil acts (for it corrupts good)
3. Therefore, Evil is a being and a nature

E) 1. Nothing belongs to the perfection of the universe except what is being and a nature
2. Evil belongs to the perfection of the universe of things
3. Therefore, evil is a nature

Opposites are known through the other. Darkness is known through light, evil is known from the nature of good

The being and perfection of any nature is good. Therefore, evil cannot signify being or any form of nature.

Evil is neither a being nor a good. Being is good, without being there is no good and without good there is no being.

Replies to objections

A) Good and evil are said to be genera, not simply, but in regard to contraries. As every form has the nature of good, so every privation has the nature of evil.

B) Good has an end but the country of good (evil) is different, not in its end but in the fact it has no end at all

C) Between good and evil there is a medium (in moral evil). From moral evil there can be a return to the good. But from physical evil (i.e. blindness) there can be no return to good (sight).

D) A thing acts three ways:

1. Formally
i.e. whiteness makes white
- evil formally acts as a privation as it corrupts goodness

2. Effectively
i.e. a painter makes the wall white

3. Final Cause
- The end is said to effect by moving the efficient cause

Evil does not effect anything as a privation. Every action comes from some form (evil has no form). Evil acts only by some good joined to it.

E) Evil only exists accidentally and acts only as some good joined to it. Therefore, evil does not belong to the perfection of the universe as it has no being.