[The notion of equilibrium] is a notion which can be employed usefully in varying degrees of looseness. It is an absolutely indispensable part of the toolbag of the economist and one which he can often contribute usefully to other sciences which are occasionally apt to get lost in the trackless exfoliations of purely dynamic systems.

The perception of potential threats to survival may be much more important in determining behavior than the perceptions of potential profits, so that profit maximization is not really the driving force. It is fear of loss rather than hope of gain that limits our behavior.

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.

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.

Economic progress means the discovery and application of better ways of doing things to satisfy our wants. The piping of water to a household that previously dragged it from a well, the growing of two blades of grass where one grew before, the development of a power loom that enables one man to weave ten times as much as he could before, the use of steam power and electric power instead of horse or human power - all these things clearly represent economic progress.

We never like to admit to ourselves that we have made a mistake. Organizational structures tend to accentuate this source of failure of information.

Without the heroic, man has no meaning; without the economic, he has no sense. Economic man is most likely to be economic woman - a good wife, pulling the coat tails of her heroic husband, checking his extravagances of speech and action with words of caution and good sense. But without the heroic coat tails to pull, life for both of them would be dull and savorless indeed.