Years ago I worked in an Astronomy department. One of the students there was a man with cerebral palsy. He was not seriously disabled, but he had some problems with controlling his limbs, especially if he was excited or thinking very hard. Once, when talking to a distinguished visitor, he became so involved in the discussion that he suddenly threw a cup of hot coffee all over the eminent professor’s front. The professor was very nice about it and simply helped to clear up the mess.
The problem was that the guy’s brain could easily cope with holding a cup of coffee, but not with doing advanced maths at the same time. And yet, we all tend to think that the human brain is good enough to understand the secrets of the universe. There’s no real reason for that to be true. As Heisenberg pointed out, the universe may be far stranger than we can think. Most of us handle our coffee well, most of the time. But we shouldn’t put too much faith in it.