The cause of lightning was once thought to be God's wrath, but turned out to be the unintelligent outcome of mindless natural forces. We once thought an intelligent being must have arranged and maintained the amazingly ordered motions of the solar system, but now we know it's all the inevitable outcome of mindless natural forces. Disease was once thought to be the mischief of supernatural demons, but now we know that tiny, unintelligent organisms are the cause, which reproduce and infect us a...