“Man was formed with an understanding for the obtainment of knowledge; and happy is he who is employed in the pursuit of it. Ignorance is in its nature unprofitable; but every kind of knowledge may be turned to use. Diligence is generally rewarded with the discovery of that which it seeks after; sometimes of that which is more valuable.”

Act II, scene iv.
Manfred (1817)

Dijkstra (1998) https://www.cs.utexas.edu/users/vl/notes/dijkstra.html
1990s

"On the Harmony of Theory and Practice in Mechanics" (Jan. 3, 1856)

The Crystal Spirit : A Study of George Orwell (1966), Ch. I : The Man I Remembered, p. 3
Context: Orwell can only be understood as an essentially quixotic man. … He defended, passionately and as a matter of principle, unpopular causes. Often without regard to reason he would strike out against anything which offended his conceptions of right, justice and decency, yet, as many who crossed lances with him had reason to know, he could be a very chivalrous opponent, impelled by a sense of fair play that would lead to public recantation of accusations he had eventually decided were unfair. In his own way he was a man of the left, but he attacked its holy images as fervently as he did those of the right. And however much he might on occasion find himself in uneasy and temporary alliance with others, he was — in the end — as much a man in isolation as Don Quixote. His was the isolation of every man who seeks the truth diligently, no matter how unpleasant its implications may be to others or even to himself.

Source: The Power-House (1916), Ch. 3 "Tells of a Midsummer Night"
Context: I read now and then in the papers that some eminent scientist had made a great discovery. He reads a paper before some Academy of Science, and there are leading articles on it, and his photograph adorns the magazines. That kind of man is not the danger. He is a bit of the machine, a party to the compact. It is the men who stand outside it that are to be reckoned with, the artists in discovery who will never use their knowledge till they can use it with full effect.

Source: The Economics of Welfare (1920), Ch. 1 : Welfare and Economic Welfare, § 1

Source: The Principles of Agriculture, 1844, Section I: The fundamental principles, p. 1.

Introduction
Popular Astronomy: A Series of Lectures Delivered at Ipswich (1868)

Education: Intellectual, Moral, and Physical (1861)
Context: If there be an order in which the human race has mastered its various kinds of knowledge, there will arise in every child an aptitude to acquire these kinds of knowledge in the same order. So that even were the order intrinsically indifferent, it would facilitate education to lead the individual mind through the steps traversed by the general mind. But the order is not intrinsically indifferent; and hence the fundamental reason why education should be a repetition of civilization in little.<!--p.76