Warren is one of the best learning machines on this earth....Warren's investing skills have markedly increased since he turned 65. Having watched the whole process with Warren, I can report that if he had stopped with what he knew at earlier points, the record would be a pale shadow of what it is.
If you have enough sense to become a mental adult yourself, you can run rings around people smarter than you. Just pick up key ideas from all the disciplines, not just a few, and you're immensely wiser than they are.
I constantly see people rise in life who are not the smartest, sometimes not even the most diligent, but they are learning machines. They go to bed every night a little wiser than they were when they got up, and boy, does that help, particularly when you have a long run ahead of you.