It seems likely that there are innate differences of intelligence. But it seems almost impossible that a matter so many-
“One doesn’t have to be a physicist or even a gardener to realize that the quality of an entity as diverse and complex as soil depends upon … [a] large number of variables … [Yet] it is only in recent years that the hunt for single-value characterizations of soil properties has been virtually abandoned.”
The single-valued I.Q. is still far from being abandoned, even though this kind of criticism is leading, slowly and belatedly, to attempts to investigate such things as “creativity”. However, the success of thes attempts is very doubtful: creativity is also many-sided and complex.
We must be clear that it is perfectly possible that an intellectual giant like Einstein may have a comparatively low I.Q. and that among people with an unusually high I.Q. talents of the kind that lead to creative World 3 achievements may be quite rare, just as it may happen that an otherwise highly gifted child may suffer from dyslexia. (I have myself known an I.Q. genius who was a blockhead.)