Comparing Darwin to a real math and physics genius
Darwin wrote of himself:
I attempted mathematics [at Cambridge University ], and even went during the summer of 1828 with a private tutor (a very dull man) to Barmouth, but I got on very slowly. The work was repugnant to me, chiefly from my not being able to see any meaning in the early steps of algebra. This impatience was foolish, and in after years I have deeply regretted that I did not proceed far enough at least to understand something of the great leading principles of mathematics; for men thus endowed seem to have an extra sense. But I do not believe that I should ever have succeeded beyond a very low grade.
Autobiography (p. 58 of the 1958 Norton edition)