It’s worth reading this post by Mike Dobbins (a theist apologist) about whether atheists have a mere lack of belief in the existence of God, or a belief in the non-existence of God.
Atheists stating atheism is nothing more than a ‘lack of belief in God’ are simply using that definition as a cop-out. They are hiding behind an impotent definition of atheism so they won’t have to confront what they actually believe about God. Atheists are quite willing to accept they have disbeliefs regarding other supernatural phenomenon and the Flying Spaghetti Monster. It is time they became reconciled to the fact that they they don’t believe in God as well.
I think this is fair. I’m certainly willing to lay my cards on the table and make the stronger of the two claims – that I disbelieve in God. That is, I believe there is no god (reasonably defined) of any kind.
I do, however, see a place for the ‘lacking belief in God’ definition when describing atheists as a whole. What is the necessary condition that someone must satisfy in order to correctly be described as an atheist? In my opinion, it should be that they don’t believe in God, not that they disbelieve in God. In practice of course, most atheists probably do hold a belief that there are no gods, but I would still resist the idea that someone can deduce what someone believes solely on account of their being an atheist.
As far as the charge of “cop-out” goes, I would perhaps agree. It’s one thing to attack your opponents arguments, but it is a much harder task to put forward your own and defend them. I have come across plenty of atheists who claim they only lack belief in God, and some who bizarrely claim to lack any beliefs at all! I suspect the latter is down to them defining “belief” as some proposition held to be true in the absence of evidence, or as a synonym for “faith”, but this just isn’t a reasonable definition.
Finally, on a related note, just because an atheist believes that God doesn’t exist doesn’t mean that they ought to defend it every time we question or debate a theist. It is fine to demonstrate that theism fails, or that the arguments for theism fail. If successful, we’ll be in a state of ‘lacking belief’. If we then want to take that to the next level and challenge ourselves, let’s let the theist hold our disbelief up to scrutiny just as we’ve done to their belief. There’s nothing of value to be lost by questioning ourselves.