A problem with some Anselmian ontological arguments is bridging the gap between God existing in the mind and God existing in reality. Perhaps this argument, or something like it avoids this problem:

1. There is something in reality which is also the highest object of human thought.
2. The highest object of human thought is that than which nothing greater can be conceived.
3. God is that than which nothing greater can be conceived.
4. Therefore, God exists.