The power of abstraction is that it allows us to ignore irrelevant details and focus on the essential aspects of a problem.

The secret of change is to focus all of your energy not on fighting the old, but on building the new.

The great secret that all old people share is that you really haven't changed in seventy or eighty years. Your body changes, but you don't change at all. And that, of course, causes great confusion.

The best preparation for tomorrow is doing your best today.

每一个他者都是完全的他者。