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 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.

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

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.

The social dynamics of human history, even more than that of biological evolution, illustrate the fundamental principle of ecological evolution - that everything depends on everything else. The nine elements that we have described in societal evolution of the three families of phenotypes - the phyla of things, organizations and people, the genetic bases in knowledge operating through energy and materials to produce phenotypes, and the three bonding relations of threat, integration and exchange - all interact on each other.

[on the theory of the firm] It is exactly analogous to the analysis of the reactions of a consumer by means of indifferent curves. Indeed, a consumer is merely a 'firm' whose product is 'utility.'

Anyone who believes exponential growth can go on forever in a finite world is either a madman or an economist.