The social sciences have been divided into departmental silos for far too long, yielding at best partial insights among economists, political scientists, and sociologists. The most influential attempt at integration, economic imperialism, distorted our understanding of processes with looser constraints than among producers in competitive markets. The theory of spontaneous order, first developed by Michael Polanyi and Friedrich Hayek in the 1940s and 1950s, offers a more promising framework for interdisciplinary social theory. It does not rely on unrealistic assumptions of maximizing behavior, unlike rational choice theory borrowed from neoclassical economics. It is compatible with psychological findings on human behavior, recognizes the heterogeneity of resources and constraints in different social orders, and pays attention to historical processes of individual and social learning. Spontaneous-order theory provides a unified framework for four key orders of decentralized human interaction: the cultural, democratic, market, and scientific orders. Each such order is associated with order-specific resources. Order participants face constraints, but these constraints are not always the same, even within the same order. For example, competing producers face relatively tight break-even constraints, which make their actions unusually predictable. In contrast, consumers in a market order or politicians in a democracy face looser constraints. They are not compelled to maximize utilities or votes, but their relatively loose constraints nevertheless make many potential actions infeasible. Consumption requires money and policies require votes and resources. Exact predictions become impossible, but spontaneous-order analyses offer the promise of more reliable pattern predictions.