Saint Anselm proof for the existence of God

Definition of God. The idea/concept of God is the idea of a being than which none greater can be conceived. None greater is possible.

Premise 1) God exists in the mind or understanding.
Premise 2) God might exist in reality
Premise 3) If something exists only in the mind and yet might exist in reality as well, then it would be greater(more nearly perfect) than it is by only existing in the mind.
Premise 4) Suppose(for reductio ad absurdum) that God exists only in the mind.
Premie 5) Thus God might have been greater than he/she is (follows from premise 2-4)
Premise 6) Thus, God is a being than which a greater can be conceived.
Premise 7) Thus by the definition of the idea/concept of God, the being than which none greater can be conceived is a being than which a greater can be conceived.
Premise 8) but 7 is a contradiction and it validly follows from 4
Premise 9) Hence 4 is necessarily false
Premise 10) Thus, God exists in reality as well as the understanding.

An interesting argument that I'm studying in School. I thought I'd through it up here for all you believers out there. The argument is definitely Valid but is it sound? I'm not so sure about premise 3. In that something is considered more perfect if it exists in the mind and might exist in reality than if it just existed in the mind.

i understand your questions with premise 3 but if a higher power can do more than just exist in your mind, it has the ability to do more things. so that opens up more probability. like more on the ratio between Perfect/imperfect. if you dig what im saying..

The problem there is, it doesn't prove anything in particular... To restate

1) God is conceptually perfect
2) God either exists in reality or within the mind of man
3) A real entity is more perfect than an unreal entity
4) Therefore god exists

Clearly, Saint Anselm forgot to scrape the ergot of his rye a bit too often... The logic only works if you start with the assumption that a perfect entity named god exists. You can take the same path in a totally different direction though...

1) God is conceptually perfect
2) Perfection is an abstract concept
3) Abstract concepts exist only in the human mind
4) Therefore, a perfect god can only exist in the human mind

See?

yes i agree. and i love the lsa reference.