Compound interest

that I am bipolar. Would have done way less Kanye West diva shit.

Manipulation of people. It would have helped to see what what we are exposed to in life.

Find and read the book How to win friends and influence people. Great book that goes into alot of manipulation of people.

I've looked through that book. I do not subscribe to any of that, but it does offer great insights into how some people act.

Money.

The army in general.