Aristotle

1. Four Causes

1.1. Material

1.1.1. Matter or substance

1.2. Efficient

1.2.1. The cause

1.3. Formal

1.3.1. What makes it what it is

1.4. Final

1.4.1. Its purpose

2. Prime Mover

2.1. Something that causes motion and change in the universe

2.2. Necessary existance

2.3. Is THE Final cause of the universe

2.4. Considered to be God

2.5. Is separate from the universe

2.6. Only activity is thinking about himself

3. Differences from Plato

3.1. Studies the physical world, not a world of ideas

3.2. Rejects the theory of Forms

3.3. Rejects Plato's idea of the eternal soul (Aristotle says the soul is mortal)

4. Criticisms

4.1. Aristotle's God appears impotent, he can't interact with the world

4.2. Relationship between the Prime Mover and the universe is unclear

4.3. Is there a clear final cause of the universe?

5. Influence on Christianity

5.1. HUGE! (especially in Catholicism)

5.2. Most of Aquinas' philosophy was a development of Aristotles' (cosmological)

5.3. Prime Mover idea developed into the current ideas about the nature of God