"Moral relativism" is the belief that there is no truth when it comes to morality and faith. "Intellectual relativism" takes this flawed notion to the extreme...demanding that all ideas are equal and valid (more likely that my idea is equal to yours despite its merits). It is the belief that an idea is right because I think it is right and nobody has the right to point out that it is wrong.
Some ideas are just plain wrong. Evolution exists just as the sun rises every morning. Oh, and the world is not 6,000 years old.
Society's pursuit of truth and understanding demands intellectual honesty.