Look at these two statements:

1. I believe that God exists
2. I do not believe that God exists

On the face of it they appear to be two sides of the same coin. They are opposites. Or are they? In reality, what the first statement, the position of Christians, Muslims and other theists, is telling us is this: a person who believes in God has come to this position by being convinced in some way that God exists. Meanwhile the second statement, the position of atheists, is that he or she has not been convinced, and therefore does not believe in the existence of God.

All an atheist claims is 'I do not believe that God exists' and this in itself is an undeniably true statement because it says nothing about proof of the existence of God, only that the person does not believe. In the same way, theists undeniably do believe that God exists. But as before, this does not have anything to do with proof of God's existence.

Proof is, however, an important aspect when considering why anyone does or does not believe in the existence of God.

Theists, those who believe in God, must bring forward reasons for their belief in God. This is because their belief, their faith, is a belief in a specific definition of God. For Christians it is the God whose actions are described in the Bible. For Muslims the Qur'an shapes their understanding of what God is. When saying 'I believe that God exists', it is therefore an absolutely fundamental requirement that you must bring to the table your reasons for holding this belief. If there were no reason to believe in the Christian God, why not believe in the Norse Gods instead?

Are these 'reasons to believe' proof for the existence of God? A Christian will tell you that they are. So will those of other religions. Even something as seemingly straightforward as 'creation proves that God exists' is a statement of several things:

1. I believe that God exists
2. I present this observation/evidence to you as proof of God's existence
3. This is one of the reasons I believe in the God described by my religion

Atheists, however, are absolutely not required to prove that God does not exist. Why not? Because any such assertions would, of necessity, have to be in terms of the claims made by theists. Let's take the previous example: 'creation proves that God exists'. An atheist might say simply, 'I am not convinced by your argument'. Yes, both sides might go into more detail, but it is detail which must be provided by the theist, and which an atheist will (if he continues to be an atheist) reject as proof of God's existence, for whatever reason.

Yes, atheists can and do provide proof that particular claims made by theists are incorrect, but we do not have to provide cast-iron proof of the non-existence of God. The existence of God isn't something an atheist thought up in the first place, so why even attempt to prove that a god, any god does not exist? The only reason atheists debate with Christians is to refute Christian dogma. There is no atheistic proof for the non-existence of God, just as there is no atheistic proof for the non-existence of fire-breathing dragons. All we assert is that there is a lack of evidence to support any such claims (for God or dragons). Then given this absence of evidence, why should atheists believe in God?

Evolution, despite what theists vehemently claim, is not something used by atheists to attempt to prove that God does not exist. Evolution says nothing about God, nothing at all. Physics, biology, chemistry, and all the other sciences so readily attacked by theists, are not atheistic plots to prove that God is not there. Atheists do defend the sciences, but this is because theists try to discredit them so frequently. In and of itself, defending science is nothing to do with the existence of God.

If atheists were required to provide proof of something in which they do not believe, where would this end? Would Christians be required to prove that their God is not purple if someone claimed he was? Would Muslims have to present evidence that Allah does not eat chocolate cake on Wednesdays? The burden of proof is always, always on the person making the claim. 'A purple God' may seem ridiculous to Christians. But 'God' seems equally preposterous to atheists.

Theists believe that God exists, so let them prove it, and when the proof is convincing enough, atheists will readily accept that proof. That almost goes without saying - I don't believe in God, but if you provide enough proof to convince me that he exists, I will believe in him. Conversely, theists do believe in God, and provide their reasons, their 'proof' that this is so, and it follows that if each one of their reasons is examined and proved to be incorrect, the theist should become an atheist, simply because they will have no valid reason to believe.

This is partly why there is such debate between theists and atheists. Theists present their evidence, knowing that if any part of that evidence convinces someone that God exists there will be one less atheist in the world. Atheists have a seemingly far tougher job - they must dismantle everything which convinces a theist of God's existence. (It's often the case that once you undermine one part of a person's faith in God, the whole thing falls like a house of cards, but that isn't something for discussion here.)

The burden of proof has to be on theists, purely because it is the theists who define who/what/where/why their particular God is. If someone asks you to prove that God does not exist, all that is necessary is to respond with 'define your God'. If they refuse to do so, you would be perfectly within your rights to make up your own definition of God and easily refute it... which of course the theists would love you to do because they then say, 'But that's not who God is. God is...' and go on to define what they mean when they say 'God'.

If all else fails, if someone tells you that you, an atheist, must provide proof that God does not exist, that it is your burden of proof to do so, here's one simple response: 'Sorry, I don't believe that either'.