A friend to all is a friend to none.

Men make history and not the other way around. In periods where there is no leadership, society stands still. Progress occurs when courageous, skillful leaders seize the opportunity to change things for the better.

If there is no wind, row.

Knowledge is a treasure, but practice is the key to it.

I have a great respect for incremental improvement, and I've done that sort of thing in my life, but I've always been attracted to the more revolutionary changes. I don't know why. Because they're harder. They're much more stressful emotionally. And you usually go through a period where everybody tells you that you've completely failed.

Do not dwell in the past, do not dream of the future, concentrate the mind on the present moment.