Descartes' Meditations | The Syllogist

Descartes' Meditations made Simple

Proofs of God

"The Cosmological Proof" - Meditations #3

1. Everything has a cause.

2. The level of reality of cause is greater than or equal to the level of reality of effect.

3. The level of formal reality of cause is greater than or equal to level of objective reality of effect.

4. The idea of God exists in some mind.

5. The idea of God has infinite objective reality.

6. Therefore, this idea has a cause with infinite formal reality

7. The only thing with infinite formal reality is God

8. God must exist.

The "Ontological Proof" -- Meditations #5

(Triangle)
1. Having 3 sides is part of a triangle's essence.
2. All polygons with 3 sides have 3 angles.
3. Having 3 angles is part of a triangle's essence.
4. If A is an essence of B, B must possess the property of A.
5. A triangle necessarily has 3 angles.

(God)
1. Having all of the perfections is part of God's essence.
2. Existence is a perfection.
3. Existence is part of God's essence.
4. If A is an essence of B, B must possess the property of A.
5, God necessarily exists.

Either that there is some difference between the proof that a triangle has three sides, or that God necessarily exists.

Perfect Island Objection -- Gaunilo

1. Having all of the perfections is part of a perfect island’s essence.
2. Existence is a perfection.
3. Existence is part of God's essence.
4. If A is an essence of B, B must possess the property of A.
5. A perfect island necessarily exists.

1-5 seems absurd.