Atheism and Agnosticism are not interchangeable or even similar in any way, except when contrasting all schools theistic and all schools which could be considered--within the context that a lack of specific belief is definitive--not theistic. There are, in fact, different schools of both Agnosticism and Atheism that fall not so easily under the umbrage commonly assigned them and are hardly comparable. While examining the various schools of Agnosticism and Atheism, there are specifics in regards to an individuals personal reasoning which are not only important but nearly essential to take in to account.

From one of a theistic school of thought, it may be uttered that the only important destination is that in which the "Atheist" has proclaimed that they, in some way, lack a faith in god. The larger, and dare I say, more important differences between a simple lack of faith and an anti-faith is generally left as an obscure and unimportant distinction.

To clarify my case, I will share a somewhat unpopular opinion of my own. As an Agnostic, I feel that, in regard to aspects of faith (an important theistic distinction), Atheists have more in common with Theists than they do with Agnostics. That is to say, Atheists have faith that there is no sort of God, higher power or deity without any reasonable sort of proof. I feel that this sort of blind faith is silly no matter where you deign to place your bets and that comparing an honest, spiritual profession of ignorance to an outright baseless denial of all things unknown is rather tacky.