I have my own (unoriginal) answer, outlined in this post.
In short, I think it’s important to distinguish learning ability and competence. The reason why Magnus Carlsen towers above me in chess is because he has more practice, not because he’s superintelligent.
However, I also think that even putting this distinction aside, we shouldn’t be surprised by large variation. If we think of the brain like a machine, and cognitive deficits as parts being broken parts in the machine, then it is easy to see how distributed cognitive deficits can lead to wide variation.
I have my own (unoriginal) answer, outlined in this post.
In short, I think it’s important to distinguish learning ability and competence. The reason why Magnus Carlsen towers above me in chess is because he has more practice, not because he’s superintelligent.
However, I also think that even putting this distinction aside, we shouldn’t be surprised by large variation. If we think of the brain like a machine, and cognitive deficits as parts being broken parts in the machine, then it is easy to see how distributed cognitive deficits can lead to wide variation.