Until my recent foray in the blogosphere, I was ill-prepared for the depth and magnitude of this issue. There are a lot of confused people out there.
Harry's post was actually well written and I do not have much to add to it. Still I want to present a short analysis of the issues of Emunah, perhaps it can help some people reduce the confusion.
All the players in the game must be aware of one principle: There is not any and cannot be any irrefutable empirical proof of G-d.
How do I know?
G-d told me. (Of course, for those of you who do not believe in G-d, then the Torah was written by a deranged prankster. Thus, a deranged prankster told me.)
Shmos 33:20. Here G-d (or the prankster) tells us: כ ויאמר לא תוכל לראת את-פני כי לא-יראני האדם וחי:
And He said, "You are unable to see My face, for a man cannot see Me and live."
Although there are many ways to understand this pasuk, one simple understanding is that if there were irrefutable evidence of G-d, and thereby we would be able to "see" Him, we would lose our free-will, our bechira. Not having free-will is tantamount to death.
And so, for our own benefit, G-d does not allow us to "see" Him with unequivocal clarity. This being the case, it is impossible to prove the existence of G-d to another person. Don't bother trying.
Still, G-d leaves His imprint all over the place. Anybody who looks for G-d can find Him. And therefore, a person is capable of proving to himself, and only to himself, the existence of G-d.
Who told me this?
King David told me this. He wrote it for me in Tehillim 145:18 and he left instructions to read it over at least twice a day. There he wrote: קרוב ה' לכל-קראיו לכל אשר יקראהו באמת:
Hashem is close to all who call Him, to all those who call Him in earnest.
What does this mean? It means that anybody who looks for G-d can find Him, provided one thing:
He calls in earnest. In other words, he wants to find Him.
And herein lies the key to Emunah - one will never believe in G-d unless one wants to believe in G-d!
What comes out is a true example of G-dly irony. Only a believer will find proof of G-d - and plenty of it. A non-believer will find nothing. This is because G-d is actually a real nice Guy and gives everybody what they want. If you want to find Me - here I am. You don't want to find me, you never will.
Thus Rabbi Avigdor Miller ZT"L says in his tapes that a watermelon is a proof of G-d. To someone like me who is interested in seeing G-d, I agree with him and see G-d in a watermelon. Also in apples and oranges, chickens and eggs, birds and bees, flowers and trees, mountains and seas, and, more than anything, in children. (For the life of me, I cannot fathom how anybody who ever produced a child of their own can doubt G-d; but that's just me.) But the scoffer scoffs at Rabbi Avigdor Miller and at the watermelon and at the children and at everything else and believes in the "fossil record". (Incidentally, I see G-d in the fossil record, as well.)
This a variation of the age old adage:
To the believer, there are no questions and to the non-believer there are no answers.
So a non-believer is somebody who doesn't want there to be a G-d. And a doubter is somebody who is not sure he wants there to be a G-d.
The question boils down not to: "Is there a G-d or is there no G-d?" but rather to: "Do I want a G-d or do I not want a G-d?" Or, as Tommy Lee Jones would say: "Can I handle a G-d?"
"What's in it for me?"
"Am I better off with a G-d or am I better off without one?"
"Is G-d good for me or not?"
Or - lets shorten that last question a bit: "Is G-d good or not?"
What is G-d, anyway?
Well, according to Rambam's 13 principles, G-d is: the supreme Creator of all that exists (Priciple 1), unique in his Oneness (Principle 2), and has no tangible form and thus cannot be perceived by Humans (Principle 3).
Most of us can handle that.
Why? Because it does not have much to do with us.
But let's move on.
According to Rambam, G-d also gave us the Torah through Moses (Principle 8), is aware of all of our actions (Principle 10), and will reward us for obeying Him and punish us for disobeying Him (Principle 11).
This means we have rules to live by and we are accountable to G-d for how we live up to these rules. It means that we cannot do whatever we want. It also means that when we leave this world, the game is still not over.
Some of us like this deal. We want G-d to be here for us and we are willing to be here for Him. And because this is what we want, we are willing to believe.
Others cannot handle this deal. As we say to the bee: We don't want your honey and we don't want your sting. They do not want G-d. And so they are not prepared to believe.
But, either way, nobody can prove it. It's not what you believe. It's not watermelons or fossils. It's what you want for yourself.
And so, G-d (or the deranged prankster) tells us in Parshat Bechukosai: If you walk in My ways and do My bidding - if you include Me in your life - I will make life very pleasant for you. It comes at a price but it is well worth it.
But, if you leave me out and refuse to look for Me, then you will never find me. If you want a G-dless existence I will give you a G-dless existence. And you can do whatever is within your power to do. I will not interfere. And you will become part of the "fossil record".
Sounds to me like the world is just one big foxhole.