Aphorism # 4:
Knowledge and courage contribute in turn to greatness. Since they are immortal, they immortalize. You are as much as you know, and a wise person can do anything. A person without knowledge is a world in darkness. Judgment and strength, eyes and hands; without courage, wisdom is sterile.
I think this aphorism should be reversed depending on whom one is addressing. In the case of older, more knowledgeable people one should probably remind them that knowledge without courage has no teeth. But in the case of young people one should probably emphasize that courage without knowledge is reckless and actually quite dangerous.
I guess this comes from being a mother. You want to protect your young – especially those of us with “bad boy” young ‘uns who might take it into their heads to “change the world.”