I think you argument is with John Gray, and not the author. Mr. Gray makes the distinction that the mind servers evolutionary success, not truth, and thus shows his lack of logic or reason. And that is what the author points out.
Based on the quote of Gray in the article, Gray merely says the supposed evolution of the mind would be to have a mind that promotes survival, not philosophic truth. But that does not CONTRADICT a mind discovering philosophic truth.
“Gray has essentially said, if Darwin’s theory is true, then it “serves evolutionary success, not truth.” In other words, if Darwin’s theory is true, then it is not true.”
Saying something serves evolutionary success does NOT imply it cannot find truth.
“You are an animal. Animals only need to survive and procreate. Animals do not know scientific truths. Therefore truth, in particular scientific truth, does not exist.” - angryoldfatman
Animals DO know scientific truth, if they (as humans) work to attain it. Scientific truth merely means an acceptable (but not necessarily totally accurate) explanation for what one sees and experiences. Science does not involve itself in attaining ultimate truth. It is involved in explanations of experience that match A & B together so long as no better explanation comes along.
Evolution may or may not be a totally accurate explanation for what we see, but perfection is not attained by science. That is the realm of math, perhaps, but not science.
I feel odd making this argument, since I’m not an evolutionist. But intellectual honesty is important. God is ill served by either dishonesty or bad thinking.
In any case, the pressures that might evolve a mind have little to do with how well that mind functions in math or philosophy. More than one invention has found its best use in something the inventor did not have in mind at the time.