For me, atheism is simply the lack of belief in a god. Defining atheism, for some reason, has caused a fair bit of argument, partially because it relates to who gets the burden of proof in a debate.
Nevertheless, there are those who say that most thinking atheists are actually agnostic. Indeed, upon reading or hearing my views, some would say that I am an agnostic.
I have a lack of belief in a god, but I am not saying that there definitely is no god. Similarly, I am sure that most theists wouldn’t be so arrogant (and vacuous) as to say that there definitely is a god, yet the fact remains that they believe in one and are still called theists.
Strictly, however, the terms should be as follows:
Gnostic theist – someone who is certain that there is a god.
Agnostic theist – someone who believes in a god but is not certain that there is one and is willing to concede that there may not be a god.
Agnostic atheist – someone who lacks belief in a god but is not certain that there is not a god and is willing to concede that there may be a god.
Gnostic atheist – someone who is certain that there is no god.
I, therefore, am an agnostic atheist, but I’m extremely close to being a gnostic atheist.
The fact remains, however, that those who believe in a god but are not certain about it are still called theists. I submit that the same should go for those who lack belief in a god but are not certain that there is no god – they should be called atheists.
As to which of those strict definitions is the more rational, I contend that it is the agnostic atheist position. Simply put, this is because there is no evidence for the existence of any god, although I have many other reasons not to believe in a god. As a result, the agnostic theist position is not reasonable and therefore the gnostic theist position is almost certainly not reasonable.
However, the gnostic atheist position is hardly rational either, because there exists a possibility, however small, that there is a god. Likewise, there exists a possibility that there exists a tooth fairy. Although, as we grow up, we find that the pound coin under our pillows was put there by our parents, but what if our parents’ minds were being controlled while putting the coin under the pillow, for example.
Therefore, in conclusion, I am strictly both an agnostic atheist and an agnostic a-toothfairyist.