Marking a significant departure from most scholarship on Hobbes, this book offers new interpretations of his theories of freedom, agency, rationality, morality, psychology, and politics. Hobbes's arguments concerning many different aspects of civil society and human psychology are brought together to provide a comprehensive theory of agency. Hobbes's theory of freedom is demonstrated to be considerably more complicated than previously thought, revealing a concern with both "internal" and "external" conditions of action. On close examination Hobbes can be seen to move beyond his limited definition of negative liberty and to champion autonomous rational action. Throughout, the book evaluates the relevance of this reformulation for contemporary debates in political philosophy.