You are probably correct to suspect Grant. I know someone who is deeply familiar with the topics he often talks about and says the guy is full of crap.
Regarding wisdom which is in-born, rather than developed, Plato had a term for that. It's called anamnesis. The Meno is generally cited as the best dialogue to read in order to study the subject.
In it, Socrates demonstrates that the king's uneducated slave can intuitively grasp complex mathematical concepts through geometry.
