Am I still an atheist if I believe in a higher being?

[Homeless Nutter]

You are quite mistaken in claiming that one cannot prove the nonexistence of something.  Anything whose definition is self-contradictory cannot exist.  Thus, there are no invisible pink unicorns, because "pink" and "invisible" contradict each other.  We can also know that things don't exist that do not fit with known facts.  For example, how messed up the world is, is incompatible with a being that is omnipotent, omniscient, and perfectly benevolent, so such a being cannot exist.  We can know that Santa does not exist because people have visited the north pole and his workshop is not there.  That, though, was unnecessary, as we know it is impossible for one man to visit every house on the planet in one night, and it is impossible for a man to fit down every chimney (not to mention the fact that not every house has a chimney).  The idea that one cannot prove that some things do not exist is just false.

Logically - you can't fully prove a negative statement, because one can always find (make up) justifications for why a thing can exists. "Invisible pink unicorns"? That's easy - they're generally invisible, but sometimes they become visible (whatever - they voluntarily drop their "camouflage", or they can be seen through another dimension, they're simply very, very, very small, or some such un-disprovable assertion), and then they are pink. Sure - I can't possibly prove this, but that's beside the point. 
Santa's factory is hidden way bellow the ice. Or - it's not its actual location, as North Pole does not belong in Santa Claus' definition (many cultures have different versions, North Pole is just a modern American version).

Of course - for practical reasons we can and should consider those entities as non-existent, since there is no proof for them and there are much simpler and testable explanations of reality available. But for the purpose of pure logic - we can not prove that there is no Santa, or that I'm not Napoleon Bonaparte. Luckilly - we don't really have to.