The history of the world shows us that men are not to be counted by their numbers, but by the fire and vigour of their passions; by their deep sense of injury; by their memory of past glory; by their eagerness for fresh fame; by their clear and steady resolution of ceasing to live, or of achieving a particular object, which, when it is once formed, strikes off a load of manacles and chains, and gives free space to all heavenly and heroic feelings. All great and extraordinary actions come from the heart.

Sydney Smith (1771-1845) English clergyman, essayist, wit

Lecture (1804-1806), Moral Philosophy, No. 27 “On Habit, Part 2,” Royal Institution, London
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Collected in his Elementary Sketches of Moral Philosophy (1849).

Quoted by Theodore Roosevelt in his speech (1901-09-05), "Brotherhood and the Heroic Virtues," Grand Army of the Republic Veterans Reunion, Burlington, Vermont, collected in Roosevelt's The Strenuous LIfe (1902).