Wikipedia
Upayas is a Sanskrit word that means "approaches", "to come into any state or condition" and "to come near or towards". It also refers to methods of diplomacy found in Hinduism and Jainism texts.
Kautilya mentioned four Upayas - Sama, Dana, Behda and Danda. Sama, the first step, means conciliation or alliances. Dana, the second, means gifts or compensation. Bheda, the third, means rupture or divide and rule. Danda refers to the last step, that is force or armaments. An article on Institute for Defense Studies and Analyses website states that the 20th-century power-politics theoretician Hans J. Morgenthau suggests similar four methods in a struggle for balance of power: Divide and Rule; Compensation; Armaments; and Alliances.
These four approaches are found in the Hindu Itihasa (epics) and the Dharmasastras, as well as the Jain text Nitivakyamitra.