This One is for You, Lubos
Mathematical talent often develops at an early age. This is a common observation, to which the great Russian Mathematician Andrei N. Kolmogorov added a curious suggestion. He claimed that the normal psychological development of a person is halted at precisely the time when mathematical talent sets in.
He credited himself with a mental age of 12.
OK Lubos, how old were you when your mathematical precocity showed up?