[Jack]

if I was forced to try to give a reason, "Because there is not evidence for God's existence." However, this answer is based on a logical fallacy (from ignorance).

There are exceptions to the Appeal to Ignorance I think apply here.

Sometimes it is reasonable to argue from a lack of evidence for a proposition to the falsity of that proposition, when there is a presumption that the proposition is false. For instance, in American criminal law there is a presumption of innocence, which means that the burden of proof is on the prosecution, and if the prosecution fails to provide evidence of guilt then the jury must conclude that the defendant is innocent. Similarly, the burden of proof is usually on a person making a new or improbable claim, and the presumption may be that such a claim is false. For instance, suppose that I claim that I was taken by flying saucer to another planet, but when challenged I can supply no evidence of this unusual trip. It would not be an Appeal to Ignorance for you to reason that, since there is no evidence that I visited another planet, therefore I probably didn't do so. Similarly, when extensive investigation has been undertaken, it is often reasonable to infer that something is false based upon a lack of positive evidence for it. For instance, if a drug has been subjected to lengthy testing for harmful effects and none has been discovered, it is then reasonable to conclude that it is safe. Another example is: If there really were a large and unusual type of animal in Loch Ness, then we would have undeniable evidence of it by now. We don't have undeniable evidence of a large, unfamiliar animal in Loch Ness. Therefore, there is no such animal. As with reasoning using the closed world assumption, auto-epistemic reasoning does not commit the fallacy of Argument from Ignorance.

Logical Fallacy: Appeal to Ignorance

The reasonable conclusion of atheism is auto-epistemic and not an appeal to ignorance. If you've never investigated theology but make a definitive declaration that theology is false then you're arguing from a less reasonable position.