Perhaps you are familiar with the ontological proof of Gods existence by the medieval writter circa 1200 ad--------- St anselm
I wont re-iterate it , but I will provide you with the counter-argument. One can prove that God does not exist by appyling a few lines of philosophical logic.
1) God by defination is the greatest being which can be conceived.
2) God is the creator of the universe.
3) The greatness of this monumental task is inversely proportional to the " handicap " of the creator ie
for a weaker god to have created the universe is certainly more impressive than for a stronger god to have done so
4) The most compromised position from which god could have created the universe is that he totally lacks existence.
ie. the most amazing superlative act of greatness would have been for a nonexistent god to have created the universe.
5) Therefore god does not exist.
there you have it!
Good Luck with that...