Who was Thomas Hobbes?

Thomas Hobbes of Malmesbury (1588 – 1679) was an English political philosopher. He is distinguished by an attitude of rationalism and materialism. He thinks that most human and natural phenomena can be explained rationally and scientifically.
Although Hobbes was a prolific author who wrote treatises on many different subjects, including physics, optics, and rhetoric, his most influential work was the Leviathan, a work that set forth the seminal "social contract" theory of government authority. This theory argues that people cede a degree of personal liberty to governments in exchange for safety and security. 
Hobbes famously stated that life in a state of nature was "solitary, poor, nasty, brutish and short" and that the natural state of humanity was perpetual war. He thus advocated strong, even authoritarian, government, as necessary to restrain the naturally chaotic and selfish impulses of humanity.