The man who moves a mountain begins by carrying away small stones.

Know what you know and know that you don't know what you don't know — that is the characteristic of one who knows.

I was complaining that I had no shoes till I met a man who had no feet.

I do not enlighten those who are not eager to learn, nor arouse those who are not anxious to give an explanation themselves. If I have presented one corner of the square and they cannot come back to me with the other three, I should not go over the points again.

When it is obvious that the goals cannot be reached, don't adjust the goals, adjust the action steps.

If Language is not correct, then what is said is not what is meant. If what is said is not what is meant, then what ought to be done, remains undone.

The book salesman should be honored because he brings to our attention, as a rule, the very books we need most and neglect most.