A conceptual scheme is never discarded merely because of a few stubborn facts with which it cannot be reconciled; a conceptual scheme is either modified or replaced by a better one, never abandoned with nothing left to take its place.

The stumbling way in which even the ablest of the scientists in every generation have had to fight through thickets of erroneous observations, misleading generalizations, inadequate formulation, and unconscious prejudice is rarely appreciated by those who obtain their scientific knowledge from textbooks.

Public education is a great instrument of social change. Through it, if we so desire, we can make our country more nearly a democracy without classes. To do so will require the efforts of us all-teachers, administrators, taxpayers and statesmen. Education is a social process, perhaps the most important process in determining the future of our country; it should command a far larger portion of our national income than it does today.

Science emerges from the other progressive activities of man to the extent that new concepts arise from experiments and observations, and that the new concepts in turn lead to further experiments and observations.

Each honest calling, each walk of life, has its own elite, its own aristocracy based on excellence.

Some of mankind's most terrible misdeeds have been committed under the spell of certain magic words or phrases.

Science is a dynamic undertaking directed to lowering the degree of the empiricism involved in solving problems; or, if you prefer, science is a process of fabricating a web of interconnected concepts and conceptual schemes arising from experiments and observations and fruitful of further experiments and observations.