"Out of all of the sects in the world, we notice an uncanny coincidence: the overwhelming majority just happen to choose the one that their parents belong to. Not the sect that has the best evidence in its favour, the best miracles, the best moral code, the best cathedral, the best stained glass, the best music: when it comes to choosing from the smorgasbord of available religions, their potential virtues seem to count for nothing, compared to the matter of heredity. This is an unmistakable fact; nobody could seriously deny it. Yet people with full knowledge of the arbitrary nature of this heredity, somehow manage to go on believing in their religion, often with such fanaticism that they are prepared to murder people who follow a different one."
--Richard Dawkins