This thesis seeks to address some of the most central questions to the fields of political philosophy and political economy. First, how can social order and government rationally develop out of anarchy? Next, what acts of force, if any, are morally permissible for the State to perform in its relations with individuals, so as to maintain political legitimacy? Lastly, what policies ought the State implement to achieve the best welfare outcomes for a society? This thesis will first show that a laissez-faire capitalist social order can spontaneously emerge from a purely self-interested State of Nature, with the institution of government being a mere product of market forces. Then, this thesis will defend a theory of natural rights on the basis that persons are normatively separate, before establishing that a laissez-faire capitalist social order is uniquely in compliance with these universal moral standards of conduct that predate the institution of any government. Finally, it will be argued in this thesis that the key tenets of laissez-faire capitalism - strong individual rights to life, liberty, and property - produce maximal human welfare from both individualist and collectivist aggregations, before such conclusions are translated into a foundation for limited government. Cumulatively, these arguments serve to fortify libertarian political philosophy and demonstrate that laissez-faire capitalism is the optimal form of social order.