"In the knowledge of nature," Aristotle writes, the test of principles "is the unimpeachable evidence of the senses as to the fact." He holds that "lack of experience diminishes our power of taking a comprehensive view of the admitted facts. Hence those who dwell in the intimate association with nature and its phenomena grow more and more able to formulate, as the foundation of their theories, principles such as to admit of a wide and coherent development; while those whom devotion to abstract discussions has rendered unobservant of the facts are too ready to dogmatize on the basis of a few observations." Theories should be accredited, Aristotle insists, "only if what they affirm agrees with the facts."

“We are told ... statements that are not mathematical or logical formulae may look as if they were necessarily or certainly true, but they only look like that. They cannot really be either necessary or certain.”

“All should be well acquainted with and each in his measure actively and continuously engaged in the Great Conversation that man has had about what is and should be.”

“In the course of history ... new books have been written that have won their place in the list. Books once thought entitled to belong to it have been superseded; and this process of change will continue as long as men can think and write. It is the task of every generation to reassess the tradition in which it lives, to discard what it cannot use, and to bring into context with the distant and intermediate past the most recent contributions to the Great Conversation. ... the West needs to recapture and reemphasize and bring to bear upon its present problems the wisdom that lies in the works of its greatest thinkers and in the discussion that they have carried on.”

“Because of experimental science we know a very large number of things about the natural world of which our predecessors were ignorant. In the great books we can observe the birth of science, applaud the development of the experimental technique, and celebrate the triumphs it has won. But we can also note the limitations of the method and mourn the errors that its misapplication has caused. We can distinguish the outlines of those great persistent problems that the method ... may never solve and find the clues to their solutions offered by other methods and other disciplines.”

“Is there any such thing as "an education"? The answer that is made by the devotees of the dogma of individual differences is No; there are as many different educations as there are different individuals; it is "authoritarian" to say that there is any education that is necessary, or even suitable, for every individual.”

“We do not confine people to looking at poor pictures and listening to poor music. We urge them to look at as many good pictures and hear as much good music as they can, convinced that this is the way in which they will come to understand and appreciate art and music.”