What is missing is the proof of the opposite: that the human brain can calculate those things. Really, we have no proof either way. The ability to hand-trace c

What is missing is the proof of the opposite: that the human brain can calculate those things. Really, we have no proof either way. The ability to hand-trace computation makes the human Turing-complete. Whether the Turing machine is human-complete is an open question, and I expect it to remain so. Each side of the can think vs. can't think debate works under the assumption that Turing machines are or are not human-complete, and they mostly build their cases on that assumption while claiming the other side's is wrong (without fully proving or disproving either assumption).