The economy of the future might be called the "spaceman economy," in which the earth has become a single spaceship, without unlimited reservoirs of anything.

Don't go to great trouble to optimize something that never should be done at all. Aim to enhance total systems properties, such as creativity, stability, diversity, resilience, and sustainability - whether they are easily measured or not.

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

The controversy as to whether socialism is possible has been settled by the fact that it exists, and it is a fundamental axiom of my philosophy, at any rate, that anything that exists, is possible.

The ability to work with systems of general equilibrium is perhaps one of the most important skills of the economist - a skill which he shares with many other scientists, but in which he has perhaps a certain comparative advantage.

It is absurd to suppose we can think of nature as a system apart from knowledge, for it is knowledge that is increasingly determining the course of nature.

The only religion that still demands human sacrifice is nationalism.