Your claim, underlined in the quote below:prove that it is a mistake to think this way. Your assertion, you prove it!
The use of the word "prove" rather suggests that you don't understand what you are asking. However, either you accept the copious evidence for evolution or you don't.
If you do, then it should be apparent that we evolved to fit the environment and if you wish to posit some deliberate design or purpose, then that is your assertion, which would need additional evidence.
If you don't, then it's obvious that your position has nothing at all to do with any circularity of reasoning on behalf of others, but is actually based on a massive denial of reality.