Thomas Hobbes 
Leviathan, Or the Matter, Forme, and Power of a Common-Wealth Ecclesiastical and Civil [EPUB ebook] 

First published in 1651, a classic of political science. According to Wikipedia: ’Thomas Hobbes (1588 – 1679) was an English philosopher, remembered today for his work on political philosophy. His 1651 book Leviathan established the foundation for most of Western political philosophy from the perspective of social contract theory. Hobbes also contributed to a diverse array of fields, including history, geometry, physics of gases, theology, ethics, general philosophy, and political science. His account of human nature as self-interested cooperation has proved to be an enduring theory in the field of philosophical anthropology.’