Aquinas – Five Versions of the Cosmological Argument

Cosmological (or Contingency) Argument:

1.The universe exists.

2. It is contingent on (i.e., depends on) something outside of it for its existence or some of its characteristics.

3. God is the only being that could bring about the existence of the universe in this way.

4. Therefore, God exists.

A. The Argument from Change (or Motion):

1. Some things in the world are in motion.

2. Everything in motion was moved by something else, and that was moved by something, and so on (2-7).

3. Motion must have a starting point.

4. There must be a first mover not moved by anything else.

5. God is the only being that is capable of being an unmoved mover.

6. Therefore, God exists.

B. The Argument from Causation:

1. Everything in the world is the effect of previous causes.

2. These causes are the effects of earlier causes, and so on.

3. Causation must have a starting point.

4. There must be a first cause not caused by anything else.

5. God is the only being that is capable of being an uncaused cause.

6. Therefore, God exists.

C. The Argument from Contingency:

1. Some things in the universe are capable of existing and not existing.

2. Anything capable of both existing and not existing goes out of existence at some point.

3. If all things were capable of not existing, then there was a time when nothing existed.

4. But anything that doesn’t exist can only come into being through the agency of something that does exist.

5. Therefore, there must be something that always exists (i.e., that is necessary rather than contigent) because otherwise nothing would ever come into existence.

6. The necessity of some things that are necessary is caused by an external source.

7. There must to something necessary whose necessity is not caused by an external source.

8. God is the only being that is capable of being necessary in itself, of being the cause of the necessity and existence of all other beings.

9. Therefore, God exists.

D. The Argument from Degrees of Excellence:

1. Things have more or less of certain excellent characteristics such as goodness, truth, or nobility.

2. The words ‘more or less’ are always used in comparison to a being that has these characteristics to the highest degree.

3. Therefore, there is something true, good, and noble in the highest degree.

4. Something that has truth in the highest degree also has being in the highest degree (Ontological Argument).

5. Therefore, there is something that has being in the highest degree.

6. Anything that has a quality to the highest degree is also the cause of this quality in all other things.

7. Therefore, there is something that is the cause of being, truth, goodness, and nobility in all other things.

8. God is the only being capable of doing this.

9. Therefore, God exists.

E. The Argument from Harmony:

1. Natural objects that lack knowledge very frequently operate in the same way so as to attain the best possible result.

2. Therefore, these natural objects work toward a particular goal or end.

3. They do not work toward this goal by chance, but rather on purpose.

4. Since they lack knowledge, these natural objects must be guided by someone with knowledge and intelligence.

5. God is the only being capable of directing all natural objects toward their proper goals.

6. Therefore, God exists.