“If a big diamond is cut up into pieces, it immediately loses its value as a whole; or if an army is scattered or divided into small bodies, it loses all its power; and in the same way a great intellect has no more power than an ordinary one as soon as it is interrupted, disturbed, distracted, or diverted; for its superiority entails that it concentrates all its strength on one point and object, just as a concave mirror concentrates all the rays of light thrown upon it. Noisy interruption prevents this concentration. This is why the most eminent intellects have always been strongly averse to any kind of disturbance, interruption and distraction, and above everything to that violent interruption which is caused by noise; other people do not take any particular notice of this sort of thing.”

1950s, First Inaugural Address (1953)
Context: We must be ready to dare all for our country. For history does not long entrust the care of freedom to the weak or the timid. We must acquire proficiency in defense and display stamina in purpose. We must be willing, individually and as a Nation, to accept whatever sacrifices may be required of us. A people that values its privileges above its principles soon loses both. These basic precepts are not lofty abstractions, far removed from matters of daily living. They are laws of spiritual strength that generate and define our material strength. Patriotism means equipped forces and a prepared citizenry. Moral stamina means more energy and more productivity, on the farm and in the factory. Love of liberty means the guarding of every resource that makes freedom possible--from the sanctity of our families and the wealth of our soil to the genius of our scientists.

Often abbreviated to: Nothing great in the World has been accomplished without passion.
Variant translation: We may affirm absolutely that nothing great in the world has ever been accomplished without enthusiasm.
Lectures on the Philosophy of History (1832), Volume 1

Preface (J. B. Baillie translation), § 10
The Phenomenology of Spirit (1807)

Sermons, From Our Daily Bread

Strictly Personal, ch. 31 (1941)

"Le Contrat Social", in: Prejudices: Third Series (1922)
1920s
Context: All government, in its essence, is a conspiracy against the superior man: its one permanent object is to oppress him and cripple him. If it be aristocratic in organization, then it seeks to protect the man who is superior only in law against the man who is superior in fact; if it be democratic, then it seeks to protect the man who is inferior in every way against both. One of its primary functions is to regiment men by force, to make them as much alike as possible and as dependent upon one another as possible, to search out and combat originality among them. All it can see in an original idea is potential change, and hence an invasion of its prerogatives. The most dangerous man to any government is the man who is able to think things out for himself, without regard to the prevailing superstitions and taboos. Almost inevitably he comes to the conclusion that the government he lives under is dishonest, insane and intolerable, and so, if he is romantic, he tries to change it. And even if he is not romantic personally he is very apt to spread discontent among those who are.

Source: Election address; letter to the Lord Lieutenant of Ireland, the Duke of Marlborough (8 March 1880), quoted in The Times (9 March 1880), p. 8