Can we prove Gods existence? Consider carefully what you mean by the word proof?

Can we prove Gods existence? Consider carefully what you mean by the word proof? What level of proof is required or possible? (Consider the fact that in criminal courts we only prove beyond a reasonable doubt and in civil trials all we need is a preponderance of evidence is something more needed to prove that God exists?) In examining this question you MUST address both Anselms proof of Gods existence and the proofs of Thomas Aquinas (there are five of theseyou dont need to address each individually). By address here I mean that you should demonstrate that you know these proofs and examine them in light of the questions above.