@Kundalino: How about "magic, flying, invisible sky daddies, that exist beyond time and space is just a silly idea?

REASONS FOR NOT BELIEVING IN GOD OR GODS.
1. 2000 years of failed apologetics. Attempts to reason or rationalize god or gods into existence.
.
2. Actual Empirical Evidence that Theist Claims are wrong. Assertions about
prayer, souls, and more have been scientifically debunked. When a claim is said to have an empirical effect in the real world, it can be tested. There is no actual evidence that Theist claims are true.
.
3. The lack of empirical evidence is actually evidence for the lack of a God. Look at it this way. I have 10,000 years of no evidence at all for the existence of a God or gods. I have hundreds of thousands of failed gods, demigods, spirits, angels and the rest. I have debunked or unsubstantiated claims of miracles; none of which can stand against critical inquiry.

I will make 2 assertions. 1. Belief is allocated to the degree of evidence provided. 2.Nothing is ever known for certain. (This places "belief" on a scale from 0% to 100%. We can eliminate 100 because nothing can be known completely. We can equally eliminate the 0% for the same reason.
.
Okay, let's begin a legitimate scientific inquiry. I enter a small town at the foot of a mountain. The people of the town tell me that there is a vicious man eating bear living in a cave in the mountain. I ask around and get a whole bunch of different descriptions of the bear; even among people swearing to have seen it. I begin to question. "I wonder if the bear is really there?"
.
I decide I will find out. I go to the cave. I watch the cave, day after day after day and see no bear.

I decide to set a trap and bait the trap with berries, meat, mushrooms, and other delicious food that bears like. Still no bear. The food rots away.

I think the bear must be smart and does not want me to know he is there. I sprinkle the ground with flour so I can check for paw prints. Months go by and there are no prints in the ground.

I go to the store and I buy trail cameras and I set them up so as to cover every single inch of the entrance of the cave. The trail cameras pick up nothing.

I do this for 2000 years and there is no sign of a bear. At this point, and probably well before, I am pretty damn certain there is no bear in that cave. Still I will be careful. I get my gun and I venture into the cave. Inside the cave I see no signs of a bear. No droppings, no nesting place, no paw prints, no dead chewed animals, NOTHING.
.
I am 99.999% confident there is no bear in that cave. (But what if it is a magic bear. What if it is a bear that exists beyoned time and space and only visits for 30 minutes on Wednesday nights. What if it is invisible. What if it is hiding outside the cave and has been waiting for me to leave? Bla bla bla bla....

All of these what if's and magic assertions mean absolutely nothing to me. To my mind, and for all intent and purposes. there is no bear in that cave. If you think there is still a bear in the cave it is on you to prove it.

THIS IS EXACTLY HOW SCIENCE WORKS. Once an experiment is done and the results are negative, there is no reason to do the damn experiment again. The expected results were not there. We can move on to another experiment. If this were not the case, scientists would just keep doing the same experiments over and over and over and expecting different results.

A lack of evidence, clearly demonstrates, there is nothing there. Might there be a bear in another cave? Sure. But it is not up to me to do the work to prove it is not there. If you think there is a bear in a cave, show me some evidence. I don't have another 2000 years to look for it. Science does not have the time, energy, or man power to chase down every idiotic claim made by theists. The person making the claim bears the burden of proof. If you think there is a bear in the cave, prove it.