Science is a willingness to accept facts even when they are opposed to wishes.

That's all teaching is; arranging contingencies which bring changes in behavior.

The human species took a crucial step forward when its vocal musculature came under operant control in the production of speech sounds. Indeed, it is possible that all the distinctive achievements of the species can be traced to that one genetic change.

Old age is rather like another country. You will enjoy it more if you have prepared yourself before you go.

The simulated approval and affection with which parents and teachers are often urged to solve behavior problems are counterfeit. So are flattery, backslap-ping, and many other ways of "winning friends.

We are only just beginning to understand the power of love because we are just beginning to understand the weakness of force and aggression.

The alphabet was a great invention, which enabled men to store and to learn with little effort what others had learned the hard way-that is, to learn from books rather than from direct, possibly painful, contact with the real world.