Divide and Conquer

The maxim “divide and conquer” (divide et impera) is invoked frequently in law, history, and politics, but often in a loose or undertheorized way. We suggest that the maxim is a placeholder for a complex of ideas related by a family resemblance, but differing in their details, mechanisms and implications. We provide an analytic taxonomy of divide and conquer mechanisms in the settings of a Stag Hunt Game and an indefinitely-repeated Prisoners' Dilemma. A number of applications are considered, including labor law, bankruptcy, constitutional design and the separation of powers, imperialism and race relations, international law, litigation and settlement, and antitrust law. Conditions under which divide and conquer strategies reduce or enhance social welfare, and techniques that policy makers can use to combat divide and conquer tactics, are also discussed.