You raise a valid point but for an orthogonal question. When I first saw a calculator, as a 5 year old, I thought it was the most amazing and intelligent thing

You raise a valid point but for an orthogonal question. When I first saw a calculator, as a 5 year old, I thought it was the most amazing and intelligent thing ever. The original point discussed above was about how unnecessarily complex the brain is if its function/intelligence is so simple. We may or may not want to treat it as a benchmark, but the fact remains nobody understands it or can mimic its function even after trying for a very long time. (though believe me you, that's what most of AI is trying to do, even if in a simplistic way)