There is a popular analogy amongst the online atheist community comparing non-stamp collecting to atheism. There is an atheist who calls himself the Non-stamp collector and others who call themselves aphilatelists. The claim is that atheism is not a belief, philosophy or religion. That they don’t believe in God just like somebody could not believe in stamp collecting. The problem with this doge of intellectual burden of proof for atheist claims, and yes they do make claims, is that to be an atheist you must believe that theists and their arguments are wrong.
If someone where an Aphilatelist they would be someone who does not collect stamps. I personally do not collect stamps because it is a hobby that does not interest me. However, I do not think that stamp collectors are crazy, stupid, dangerous, delusional or wrong. I do not think that their hobby is a make believe fairytale. Some atheists, on the other hand, have said these things about theists. Even atheists who are not as confrontational and blunt as Richard Dawkins, Christopher Hitchens or John Loftus must, by virtue of being an atheist, believe that theists and their arguments are wrong about God. Often there are other beliefs tied to atheism such as naturalistic materialism which are opposed to what theists believe.
Atheists will claim that they have a non-belief, but with all the books such as “The God Delusion,” “God Is Great,” and “The Christian Delusion” which attempt to show why theists are wrong it sure does seem like atheists believe something. It this belief that theists are wrong that makes the comparison of aphilatelism to atheism a false analogy. Since atheists do indeed believe something they are responsible for defending the belief that theist’s arguments fall short of proving that God’s existence is likely and that theists are wrong to believe in God.