The Montaigne Fallacy
"The Leitmotiv [i.e., an often repeated theme] of social philosophy up to the emergence of economics was: The profit of one man is the damage of another; no man profits but by the loss of others. This is not a philosophy of social cooperation, but of dissociation and social disintegration. For the sake of expediency, we call this doctrine after its proponent, essayist Michel Eyquem de Montaigne (1533-92). In the light of this Montaigne fallacy, human intercourse cannot consist in anything but the spoliation of the weaker by the stronger."
—Ludwig von Mises. Economics as a Bridge for Interhuman Understanding