Dynamics
A wise man is cured of ambition by ambition itself; his aim is so exalted that riches, office, fortune, and favour cannot satisfy him. (La Bruyère)
Though ambition may be a fault in itself, it is often the mother of virtues. (Quintilian)
Nothing in the world is so incontinent as a man's accursed appetite. (Homer)
When he has no lust, no hatred, a man walks safely among the things of lust and hatred. (Bhagavadgita)
From the satisfaction of desire there may arise, accompanying joy and as it were sheltering behind it, something not unlike despair. (André Gide)
The desire for imaginary benefits often involves the loss of present blessings. (Aesop)
Some desire is necessary to keep life in motion, and he whose real wants are supplied must admit those of fancy. (Samuel Johnson)
Nothing great was ever achieved without enthusiasm. (Emerson)
Science is the great antidote to the poison of enthusiasm and superstition. (Adam Smith)