That's true Miso. A lot of people don't understand this. It is logically impossible for any claim to be true
no matter what.
What the Scientific Method does is allow us to make are *rational conclusions* based on available data. But, for something to be considered, "true" one must be able to at least *imagine* a *testable* scenario where the claim could be proved false. (E.g. water freezes a 4oC is a claim that can be proven false as soon as someone shows it freezes at 3oC instead.)
This is called the rule of Falsifiability.
If nothing conceivable could ever
disprove a claim, then the evidence that does exist would not matter; it would be pointless to even examine the evidence, because the conclusion is already known -- the claim is invulnerable to any possible evidence.
This would not mean, however, that the claim is true; instead it would mean that the claim is meaningless. This is so because it is impossible -- logically impossible -- for any claim to be true no matter what. For every true claim, you can always conceive of evidence that would make the claim untrue -- in other words, again, every true claim is falsifiable.
So, claiming the existence of God is meaningless, just like Gribble's Pocket Hippo (which exists, but only to atheists and only when the Hippo feels like showing itself).