Intelligent Design is the idea that life is too complicated to have just happened, something had to design it.
Most people who back up ID are theists, however, all theists do not back it up.
President Bush endorsed it as a good arguement to evolution. (
Article here)
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From my point of view:
Intelligent Design is not a theory, it is only an idea. A theory has evidence supporting it, and can be disproven. This has niether aspect.
So, if this idea is investigated, there is no way of looking for evidence for it. Even if someone can conclude that yes, we were all designed by an intelligent thing, that does not prove that that thing is any sort of god or supernatural being. There is no way of proving that that thing was not in turn, created by something else. Then you have to look for what intelligence created the intelligence that created. However, that can't be proven.
Why is it always creationism vs. evolution? And why do people view that as theists vs. atheists? An atheist can believe in creationism and a theist can believe in evolution, however, fundamental Christians constantly attack evolution for it's "Ungodliness". There is nothing "ungodly" about evolution and nothing "godly" about Intelligent Design.
However, Intelligent Design is being used by fundamentalists as some sort of scientific way of the god of the Bible in to the world. There is such a thing as a "militant atheist" as they call it, and they are trying to use evolution to incorporate atheism in to the world.
There IS evidence for evolution. Strong evidence. That is why evolution is a theory and ID is just an idea. ID does not oppose evolution or vice versa, and niether one prove there is or is not a diety.
ID should NOT be taught in schools, because it is NOT a theory, it is an idea lacking evidence.