'Leviathan' is a political treatise published in 1651 by philosopher Thomas Hobbes, which argues for a strong, centralized authority to prevent chaos and ensure peace and security in society. Hobbes introduces the concept of the social contract, where individuals surrender certain freedoms to a sovereign power in exchange for protection and order, emphasizing the need for absolute authority to maintain stability in a turbulent world. This work laid the foundation for modern political philosophy and influenced the development of state theories during the 18th and 19th centuries.