Classic economic theory, based as it is on an inadequate theory of human motivation, could be revolutionized by accepting the reality of higher human needs, including the impulse to self actualization and the love for the highest values.

The theory of Communism may be summed up in one sentence: Abolish all private property.

Being exposed to theory, stimulated by a basic love of concepts and mathematics, was a marvelous experience.

My theory about creativity is that the more money one has, the more creative one can be.

The Freudian theory is one of the most important foundation stones for an edifice to be built by future generations, the dwelling of a freer and wiser humanity.

I think also of my colleagues in elementary particle theory in many lands, and feel that in some measure I am here as a representative of our small, informal, international fraternity.

Each pursues his own theory, little solicitous to correct or improve it by an attention to what is advanced by his opponents.

It is an acknowledged truth in philosophy that a just theory will always be confirmed by experiment.

My theory is that I decided to be a writer when I was about seven, but of course it is not as simple as that. Like most writers, I had to work at other things to earn a living and wrote mainly in the evenings, often very late at night, for many years.

Postmodernism is an academic theory, originating in academia with an academic elite, not in the world of women and men, where feminist theory is rooted.

The classics of Marxism, while fully appreciating the significance of the Darwinian theory, pointed out the errors of which Darwin was guilty. Darwin's theory, though unquestionably materialist in its main features, is not free from some serious errors.

A major fault, for example, is the fact that, along with the materialist principle, Darwin introduced into his theory of evolution reactionary Malthusian ideas.

Agricultural practice served Darwin as the material basis for the elaboration of his theory of Evolution, which explained the natural causation of the adaptation we see in the structure of the organic world. That was a great advance in the knowledge of living nature.

If you start any large theory, such as quantum mechanics, plate tectonics, evolution, it takes about 40 years for mainstream science to come around. Gaia has been going for only 30 years or so.

Many, many, many small moves of many kinds can bring a way to manage change. The theory can come later.