Quote from : The Portable Atheist: Essential Readings for the Nonbeliever Book

[R]eligion was the race's first (and worst) attempt to make sense of reality. It was the best the species could do at a time when we had no concept of physics, chemistry, biology or medicine. We did not know that we lived on a round planet, let alone that the said planet was in orbit in a minor and obscure solar system, which was also on the edge of an unimaginably vast cosmos that was exploding away from its original source of energy. We did not know that micro-organisms were so powerful and lived in our digestive systems in order to enable us to live, as well as mounting lethal attacks on us as parasites. We did not know of our close kinship with other animals. We believed that sprites, imps, demons, and djinns were hovering in the air about us. We imagined that thunder and lightning were portentous. It has taken us a long time to shrug off this heavy coat of ignorance and fear, and every time we do there are self-interested forces who want to compel us to put it back on again.