Generally speaking, people are not very ardent or indomitable or energetic in their affairs when their personal passions are not engaged. Yet their personal passions, however vivid they may be, do not propel them either very far or very high unless these passions keep growing before their own eyes, unless they seem to justify themselves by being related to some greater cause for the service of mankind.
It is due to our human sense of honor that we should be in need of this stimulant. Add to passions born of self-interest the aim to change the face of the world and to regenerate the human race: only then will you see what men are really capable of.
That is the history of the French Revolution.
Its narrow-minded and selfish nature led to violence and darkness; its generous and selfless elements made its impulse powerful and great.
— Tocqueville, Quoted in John Lukacs, Alexis de Tocqueville: A Bibliographical Essay