While I do not believe that I.Q. is an absolute measure of cognitive ability, I am very open to the possibility that we all have a practical limit to our "intelligence".
I remember very little of my junior school days. I do however remember being able to do long division and multiplication, with pencil and paper. Contrast that with the lad who, struggle as he did, just could not do simple sums like 4 x 3. I am pretty sure he could have spent until hell froze over, and he still wouldn't "get it". Both frustrating, and painful, to watch. I really and truly felt for him.
By the same token, I am sure there is plenty of stuff out there that I could never comprehend, even if I had until the end of time. Stuff that others "get", without batting an eyelid.
I am pretty certain that there is a whole universe out there that is beyond the absolute limit of human comprehension. Unless some aliens come down and get us over that plateau.
