The mind itself is the medium of all knowledge, and the quality of that knowledge depends upon the quality of the mind. A dull mind will produce dull knowledge; a penetrating mind will penetrate to the heart of things.
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The whole of science is nothing more than a refinement of everyday thinking. And yet this refinement is purchased at a terrible price — the price of losing touch with the concrete and the living, and of substituting for it a pale, bloodless abstraction.
Alfred North Whitehead — The Aims of Education and Other Essays
A library is not a luxury but one of the necessities of life. And yet most men are satisfied to read what chance puts before them, without ever troubling themselves to inquire whether it is the best or the worst.
Henry Ward Beecher — Eyes and Ears
The great end of life is not knowledge but action. What men need is as much knowledge as they can organize for action; give them more and it may become injurious. Some men are heavy and stupid from undigested learning.
Thomas Henry Huxley — Technical Education