This argument largely depends on semantics, and how one defines the terms "atheist" and "agnostic". If traditional definitions are applied, that is, Atheist: One who does not believe in a god, (gods), as for the lack of emperical evidence to prove a god's existence; and Agnostic: One who doesn't know if a god exists or not, or doesn't care; then I would consider myself an atheist. However, most people don't adhere to the "traditional" definitions of these terms.
To most people, agnostic simply means to not know if THEY believe in a god or not. The concept of god cannot be proven or disproven. Emperical evidence cannot "prove" any such thing either way. A person who calls himself "agnostic", often consdiers other factors than simple emperical lines of evidence. These are usually not very well defined, and vary from person to person. If I were to use this line of reasoning, I would call myself an agnostic, if, for no other reason, it leaves the door somewhat ajar to other possibilities that science alone has not yet considered.
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