The Story of Philosophy

by Will Durant

Human behavior, says Plato, flows from three main sources: desire, emotion, and knowledge. Desire, appetite, impulse, instinct—these are one; emotion, spirit, ambition, courage—these are one; knowledge, thought, intellect, reason—these are one. Desire has its seat in the loins; it is a bursting reservoir of energy, fundamentally sexual. Emotion has its seat in the heart, in the flow and force of the blood; it is the organic resonance of experience and desire. Knowledge has its seat in the head; it is the eye of desire, and can become the pilot of the soul. These powers and qualities are all in all men, but in divers degrees. Some men are but the embodiment of desire; restless and acquisitive souls, who are absorbed in material quests and quarrels, who burn with lust of luxuries and show, and who rate their gains always as naught compared with their ever-receding goals: these are the men who dominate and manipulate industry. But there are others who are temples of feeling and courage, who care not so much what they fight for, as for victory “in and for itself”; they are pugnacious rather than acquisitive; their pride is in power rather than in possession, their joy is on the battle-field rather than in the mart: these are the men who make the armies and navies of the world. And last are the few whose delight is in meditation and understanding; who yearn not for goods, nor for victory, but for knowledge; who leave both market and battle-field to lose themselves in the quiet ...