Liberty, in philosophy, involves free will as contrasted with determinism. In politics, liberty consists of the social and political freedoms to which all community members are entitled. In theology, liberty is freedom from the effects of, "sin, spiritual servitude, [or] worldly ties."
Generally, liberty is distinctly differentiated from freedom in that freedom is primarily, if not exclusively, the ability to do as one wills and what one has the power to do; whereas liberty concerns the absence of arbitrary restraints and takes into account the rights of all involved. As such, the exercise of liberty is subject to capability and limited by the rights of others.
Philosophers from earliest times have considered the question of liberty. Roman Emperor Marcus Aurelius (121–180 AD) wrote of "a polity in which there is the same law for all, a polity administered with regard to equal rights and equal freedom of speech, and the idea of a kingly government which respects most of all the freedom of the governed." According to Thomas Hobbes (1588–1679), "a free man is he that in those things which by his strength and wit he is able to do is not hindered to do what he hath the will to do" (Leviathan, Part 2, Ch. XXI).
John Locke (1632–1704) rejected that definition of liberty. While not specifically mentioning Hobbes, he attacks Sir Robert Filmer who had the same definition. According to Locke:
John Stuart Mill (1806–1873), in his work, On Liberty, was the first to recognize the difference between liberty as the freedom to act and liberty as the absence of coercion. In his book Two Concepts of Liberty, Isaiah Berlin formally framed the differences between these two perspectives as the distinction between two opposite concepts of liberty: positive liberty and negative liberty. The latter designates a negative condition in which an individual is protected from tyranny and the arbitrary exercise of authority, while the former refers to the liberty that comes from self-mastery, the freedom from inner compulsions such as weakness and fear.