You learn from a conglomeration of the incredible past - whatever experience gotten in any way whatsoever.

Experience is the only teacher we have.

No one is ever really taught by another; each of us has to teach himself. The external teacher offers only the suggestion, which arouses the internal teacher, who helps us to understand things.

If history repeats itself, and the unexpected always happens, how incapable must Man be of learning from experience.

Men are wise in proportion, not to their experience, but to their capacity for experience.

My opportunities were still there, nay, they multiplied tenfold; but the strength and youth to cope with them began to fail, and to need eking out with the shifty cunning of experience.