“The proper functioning of the state is dependent on the proper functioning of the individual, rather than the reverse. And the proper mode of individual Being that's redemptive is Truth. Truth is the antidote to the suffering that emerges with the fall of man in the story of Adam and Eve.”

"Education for Independent Thought" in The New York Times, 5 October 1952. Reprinted in Ideas and Opinions (1954)
1950s
Context: It is not enough to teach a man a specialty. Through it he may become a kind of useful machine but not a harmoniously developed personality. It is essential that the student acquire an understanding of and a lively feeling for values. He must acquire a vivid sense of the beautiful and of the morally good. Otherwise he—with his specialized knowledge—more closely resembles a well-trained dog than a harmoniously developed person. He must learn to understand the motives of human beings, their illusions, and their sufferings in order to acquire a proper relationship to individual fellow-men and to the community. These precious things are conveyed to the younger generation through personal contact with those who teach, not—or at least not in the main—through textbooks. It is this that primarily constitutes and preserves culture. This is what I have in mind when I recommend the "humanities" as important, not just dry specialized knowledge in the fields of history and philosophy.

On poetry

Notes on Religion (October 1776), published in The Writings of Thomas Jefferson : 1816–1826 (1899) edited by Paul Leicester Ford, v. 2, p. 102
1770s
Context: Truth will do well enough if left to shift for herself. She seldom has received much aid from the power of great men to whom she is rarely known & seldom welcome. She has no need of force to procure entrance into the minds of men. Error indeed has often prevailed by the assistance of power or force. Truth is the proper & sufficient antagonist to error.

"Definitions of Poetry" (1811).
Context: Poetry is not the proper antithesis to prose, but to science. Poetry is opposed to science, and prose to metre. The proper and immediate object of science is the acquirement, or communication, of truth; the proper and immediate object of poetry is the communication of immediate pleasure.

Source: The Writings and Speeches of Daniel Webster: Diplomatic Papers and Miscellaneous Letters

Variant: "I shall not waste my days in trying to prolong them. I shall use my time." also mentioned as Jack London quote in Ian Fleming book You Only Live Twice (1964), Ch. 21 : Orbit
Source: San Francisco Bulletin in 1916. Also included as an introduction to a compilation of Jack London short stories in 1956.

Studies in Classic American Literature (1923)

Source: The Argumentative Indian: Writings on Indian History, Culture and Identity