This is a bold claim. How do you know? The brain could be magical.
I think everyone on this forum who is not a Christian can agreee that the Christian God is in some sense "magical". Further, Genesis 1:27 says "So God created man in His own image; in the image of God He created him; male and female He created them."
While this falls short of saying that, like God, humans are magical, to date we have no proof they are not.
In that case the brain might be, for example, a magic antenna to another plane.
See my comment here:
https://news.ycombinator.com/item?id=14770230
The choices are that the brain is magical or that strong AI that can do anything a human brain can do (make judgments, parse text and images, underdtand culture, communicate intelligently with humans), is in some sense inevitable.
You cannot simply discount the possibility of magic. You must let people who are committed to denying the future have their out.
If I were speaking with Lord Kelvin I would allow him the possibility that birds are magical and not subject to the laws of physics, whereas any machine humanity might ever build is - so that it is certainly possible that in 100,000 years, no one will build a heavier-than-air flying machine.
The essence of flight might be magical. So, too, the essence of thinking.