People believe in God because the world is very complicated and they think it is very unlikely that anything as complicated as a flying squirrel or the human eye or a brain could happen by chance.
In the beginning of time the great creator, Reason, made the earth to be a common treasury, to preserve beasts, birds, fishes and man, the lord that was to govern this creation … Not one word was spoken in the beginning that one branch of mankind
You and I also began with the Big Bang, because all substance in the universe is an organic unity. Once in a primeval age all matter was gathered in a clump so enormously massive that a pinhead weighed many billions of tons.
The Earth was born from debris that circled the nascent Sun. It was a planet spun from dust and rock, and one of the smaller masses that were trapped in the thrall of the Sun's attraction.