[In science any model depends on a pre-chosen taxonomy] a set of classifications into which we divide the enormous complexity of the real world... Land, labor, and capital are extremely heterogeneous aggregates, not much better than earth, air, fire, and water.

Thus we seem to be on the verge of an expansion of welfare economics into something like a social science of ethics and politics: what was intended to be a mere porch to ethics is either the whole house or nothing at all. In so laying down its life welfare economics may be able to contribute some of its insights and analytical methods to a much broader evaluative analysis of the whole social process.

[The historical] development in the international system may almost be defined as the process by which we pass from stable war to stable peace.

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.

A world of unseen dictatorship is conceivable, still using the forms of democratic government.

[The question for the behavioral disciplines is simply] what is better, and how do we get there?

General Systems Theory is a name which has come into use to describe a level of theoretical model-building which lies somewhere between the highly generalized constructions of pure mathematics and the specific theories of the specialized disciplines. Mathematics attempts to organize highly general relationships into a coherent system, a system however which does not have any necessary connections with the "real" world around us. It studies all thinkable relationships abstracted from any concrete situation or body of empirical knowledge.