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

In a world of complete economic equality, you get and keep the affections you deserve. You can't buy love with gifts or favors, you can't hold love by raising an inadequate child, and you can't be secure in love by serving as a good scrub woman or a good provider.

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

I've often said that my rats have taught me much more than I've taught them.

Any single historical event is too complex to be adequately known by anyone. It transcends all the intellectual capacities of men. Our practice is to wait until a sufficient number of details have been forgotten. Of course things seem simpler then! Our memories work that way; we retain the facts which are easiest to think about.

A culture must be reasonably stable, but it must also change, and it will presumably be strongest if it can avoid excessive respect for tradition and fear of novelty on the one hand and excessively rapid change on the other.

The strengthening of behavior which results from reinforcement is appropriately called 'conditioning'. In operant conditioning we 'strengthen' an operant in the sense of making a response more probable or, in actual fact, more frequent.