1800s: Martineau · Tocqueville · Marx · Spencer · Le Bon · Ward · Pareto · Tönnies · Veblen · Simmel · Durkheim · Addams · Mead · Weber · Du Bois · Mannheim · Elias
Value-added theory (also known as social strain theory) is a sociological theory, first proposed by Neil Smelser in 1962, which posits that certain conditions are needed for the development of a social movement.[1]