What does Sam Harris mean by saying that religions are failed sciences?

[BrianSoddingBoru4]

I don't see how can somebody think that religions are somehow failed sciences. Religions were not trying to follow the scientific method and failed at it, they were doing the opposite of the scientific method from the beginning. A failed science is perhaps n-rays or stuff like that, certainly not Christianity and Islam.

He means that religions (originally, at least) attempted to explicate the physical world. They actually did make rather fumbling attempts at scientific methodology. Since their explanations of the natural world - crop failures, rain, thunder, volcanoes, etc - turned out to be wrong, they failed.

Boru