Most people are perpetually locked in the present. Their decisions are overly influenced by the most immediate event; they easily become emotional and ascribe greater significance to a problem than it should have in reality.

Nothing is stable in the realm of power, and even closest of friends can be transformed into the worst of enemies.

Think of it this way: There are two kinds of failure. The first comes from never trying out your ideas because you are afraid, or because you are waiting for the perfect time. This kind of failure you can never learn from, and such timidity will destroy you. The second kind comes from a bold and venturesome spirit. If you fail in this way, the hit that you take to your reputation is greatly outweighed by what you learn. Repeated failure will toughen your spirit and show you with absolute clarity how things must be done.

All great leaders since Moses have known that a feared enemy must be crushed completely. (Sometimes they have learned this the hard way.) If one ember is left alight, no matter how dimly it smolders, a fire will eventually break out. More is lost through stopping halfway than through total annihilation: The enemy will recover, and will seek revenge. Crush him, not only in body but in spirit.

I am impressed when I go on the internet and see a lot of young people who've been influenced by the books, or I meet someone who tells me how it has changed their life. To me, that is much more real than sales figures.

Things like reading a book or learning a language, or taking a walk - they're not stimulating. Your mind has to sort of learn how to deal with that kind of stimulation on its own. So that's a very important form of adversity.

Grand strategy is the art of looking beyond the present battle and calculating ahead. Focus on your ultimate goal and plot to reach it.