Knowledge is gained by learning; trust by doubt; skill by practice; and love by love.

Only idiots and infants need things. The language of needs is the native tongue of socialists, therapists, and paternalists of all sorts and is addressed to needy dependents. The language of wants is spoken by self-respecting adults and is addressed to other self-respecting adults.

If he who breaks the law is not punished, he who obeys it is cheated. This, and this alone, is why lawbreakers ought to be punished: to authenticate as good, and to encourage as useful, law-abiding behavior. The aim of criminal law cannot be correction or deterrence; it can only be the maintenance of the legal order.

In the United States today, there is a pervasive tendency to treat children as adults, and adults as children. The options of children are thus steadily expanded, while those of adults are progressively constricted. The result is unruly children and childish adults.

There is no such thing as mental illness, hence also no such thing as psychotherapy.

If someone does something we disapprove of, we regard him as bad if we believe we can deter him from persisting in his conduct, but we regard him as mad if we believe we cannot. In either case, the crucial issue is our control of the other: the more we lose control over him, and the more he assumes control over himself, the more, in case of conflict, we are likely to consider him mad rather than just bad.

The FDA calls certain substances "controlled." But there are no "controlled substances," there are only controlled citizens.