I can only speak for myself, but public school did nothing for me musically. I got the impression a musical career was frowned upon. But in the arts, resistance can often be the strongest inspiration.
But, ancient Greece and ancient Rome - people did not happen to believe that creativity came from human beings back then, OK? People believed that creativity was this divine attendant spirit that came to human beings from some distant and unknowable source, for distant and unknowable reasons.

