The right to have children should be a marketable commodity, bought and traded by individuals but absolutely limited by the state.

The world moves into the future as a result of decisions, not as a result of plans. Plans are significant only insofar as they affect decisions.

One advantage of exhibiting a hierarchy of systems in this way is that it gives us some idea of the present gaps in both theoretical and empirical knowledge. Adequate theoretical models extend up to about the fourth level, and not much beyond. Empirical knowledge is deficient at practically all levels.

Theories without facts may be barren, but facts without theories are meaningless.

Every culture, or subculture, is defined by a set of common values, that is, generally agreed upon preferences. Without a core of common values a culture cannot exist, and we classify society into cultures and subcultures precisely because it is possible to identify groups who have common values.

... the fouling of the nest which has been typical of man's activity in the past on a local scale now seems to be extending to the whole world society.

Even personal tastes are learned, in the matrix of a culture or a subculture in which we grow up, by very much the same kind of process by which we learn our common values. Purely personal tastes, indeed, can only survive in a culture which tolerates them, that is, which has a common value that private tastes of certain kinds should be allowed.