Helena is right in observing that we **generally **accept the testimonial of our senses as reliable. Now that does not mean that we always, unconditionally accept them. If there is a doubt, we appeal to more sensory evidence (a mirage comes into mind).
What can we say about personal experiences? They seem to point in a certain direction, no question about that - but only for those who a-prori accept that direction. But they are unrepeatable and untransferable to others. To accept them as evidence is impossible to those who do not experience them themselves. They are indistinguishable from the dreams and assertions of someone who is delusional. (No offense intended.)
The old saying: “extraordinary claims require extraordinary proofs” has a lot of truth in it. There is no observable, repeatable, transferable evidence, which would substantiate the existence of anything supernatural.
Punkforchrist, your remark about “everything must be observable” is incorrect. No one says that. Concepts are not observable, and they exist. They exist as a mental image of something physical (the color: red, or the number of apples on a table, etc…), or may exist as pure mental constructs (fairies, angels, Hamlet, etc…).
The problem is that the supernatural “existence” is **fundamentally **different from physical and conceptual existence. It is not physical, and yet it is assumed to be able to interact with the physical world (while the physical world is unable even to observe, much less interact with it). How? There is no answer, not even in principle. We cannot say that maybe some day we shall be able to observe and verify the supernatural existence. It must be accepted on faith, and this faith is not based on prior observations, it is pure, unadulterated “blind faith”.
For some it is rational to believe it. But they cannot point to anything that would convince a skeptic. The cosmological, ontological, etc. arguments are all fallacious. If one asks for hard evidence, something testable, it is asserted that God cannot be tested, it is sinful even to attempt to test God. If someone says that they never had any experience, it is frequently asserted, that they did not try “long” enough, or never tried “hard” enough - essentially putting the blame onto the skeptic, and this tactics is quite irritating. Where does that leave the skeptic? Writes off the whole concept as unnecessary.
Anyhow… I am off for a short vacation, so have a good time.