Gravity is not visible, however it is measurable. As another example oxygen is a gas, it is not visible, but you breath it in.
I don't "believe" I have thoughts, I know I do, again they are measurable trough an EEG.
Well, I can see my mind on an X-Ray film that should be prove enough to every one that its there.
Why do I want to see a God before I believe? Simple- so I can kick his *** for all the "good" he is allowing to happen in this world!
If there would be a god, then why does he not help starving children in any part of this world. Why do they have to suffer for their parents sins, because the mother was not married to the father?!
If there is a God, then why do humans fight so many religious wars??
As a good he should not allow genocide to happen, after all we are his children right? Then explain away why he is not stopping us!
I rather believe in Science, that can be proven every step of the way, then some made up person!
The bible is nothing more then another fairy tale book, just like the brother Grimm's stories.