It is unusual to connect Thomas Hobbes's political philosophy with liberal thought. This study argues that liberal philosophy is indeed indebted to Hobbes: as a modern thinker he was the first to deduce political rights and obligations from self-interest. While we may say today that Hobbes sustains the capacity of government at the expense of democratic institutions, it is equally clear that he invented the idea of political legitimacy in the modern sense. Analyzing the tradition of natural law, the doctrine of social contract, and the sources of moral and political obligation, the study shows how Hobbes' assumptions help us to understand that there is no liberty without political authority.