Some pretty wild scholars received intensive early stimulation.
On the other hand, there are many interesting reports on the high end of the scale, involving intense early stimulation.
A very early account (1800) was given by a Dr. Witte about his son who appeared to be slow.
As a result of WitteÅs program of stimulation, the boy at six was now described as precocious.
He entered the University of Leipzig by nine, got his Ph.D. by fourteen, and became a Doctor of Law by sixteen.
Similar accounts can be obtained from the lives of famous men like Lord Kelvin (physicist), John Stuart Mill (philosopher), Mozart (musician), and Alexander the Great (general).
Ceasar, that famaous Roman Conqueror, had the special early experiences of riding into battle at the age of 3 with his uncle. However, we don't recommend for anyone to try this one at home!
NOTES: Reference for Witte and others.