Atheist vs. agnostic
What is the difference between an atheist and an agnostic? It has to do with the difference between what you believe and what you think you can prove. For any particular god that you can imagine, a "theist" is one who has a belief in that god. An "atheist" is one who does not have a belief in the god. A "gnostic" is one who believes that the god can be proved to exist, and an "agnostic" is one who believes that the god cannot be proved to exist.
Notice that the terms "atheist" and "agnostic", by these definitions, are not mutually exclusive. You could be an agnostic atheist, meaning you don't think one can prove the existence or nonexistence of gods, but you don't choose to believe in one without further proof. Many people assume that atheists believe that gods can be proved not to exist, but this isn't strictly true and there is no word to describe this. You could call such a person an "untheist", perhaps. Or, you could just call such a person a "gnostic atheist", one who doesn't believe in a god and thinks that his non-belief can be proved.
So there are four possible ways one could be.
- Agnostic-Theist: believes god exists, but it can't be proved
- Gnostic-Theist: believes it can be proved that gods exist
- Agnostic-Atheist: does not believe god exists, but it can't be proved
- Gnostic-Atheist: believes it can be proved that god does not exist