Positive-Sum Growth Overturned Zero-Sum Thinking

For most of history people experienced the world as zero-sum, believing one person or kingdom could grow richer only by making another poorer, but Adam Smith and others introduced the revolutionary—simultaneously economic, ethical, and religious—idea that the whole pie can grow so everyone can profit at once; this insight has so far proven correct for humans even if not for other animals, yet remains very hard to grasp.