Many social practices essential to the welfare of the species involve the control of one person by another, and no one can suppress them who has any concern for human achievements

A disappointment is not generally an oversight. It might just be the best one can do the situation being what it is. The genuine error is to quit attempting.

Many instructional arrangements seem "contrived," but there is nothing wrong with that. It is the teacher's function to contrive conditions under which students learn. It has always been the task of formal education to set up behavior which would prove useful or enjoyable later in a student's life.

Better contraceptives will control population only if people will use them. A nuclear holocaust can be prevented only if the conditions under which nations make war can be changed. The environment will continue to deteriorate until pollution practices are abandoned. We need to make vast changes in human behavior.

Do not intervene between a person and the consequences of their own behavior.

We admire people to the extent that we cannot explain what they do, and the word 'admire' then means 'marvel at.'

A child who has been severely punished for sex play is not necessarily less inclined to continue; and a man who has been imprisoned for violent assault is not necessarily less inclined toward violence.