Because things evolve.
Why not just depend upon Natural Selection to evolve the ideal rate of mutation?
There's your answer.
How do you select for something that is supposed to be random?
Ah, the age of enlightenment I think therefore I am how could any bolder statement be made.
But the question, why do we think?, has yet to be answered.
So we turn to science, but it can only give the absolutes as provided by nature, the laws that describe the Universe and the physical. How can science describe the intangibles, i.e. thoughts?
Evolutions Big Bang Thoughts just appeared just like the Universe. Just accept it now and science will prove this later. This surly could not be based on faith.
But even if this were to be proven true our intelligence came from nothing? How could this be trusted coming from our own minds?
For science to prove this, nature itself would need intelligence, and we would then need to prove that nature happened by chance.
Or maybe we could just come up with some politically correct words to better describe ID>
Are you are arguing that there is no intelligence behind your own intelligence. LOL!