Liberty is generally considered a concept of political philosophy and identifies the condition in which an individual has the ability to act according to his or her own will.

Political philosophies rooted in individualism and socialism often conceive of liberty differently; individualist and liberal conceptions of liberty relate to the freedom of the individual from outside compulsion; a socialist perspective, on the other hand, regards liberty as the equal distribution of power, arguing that liberty without equality amounts to the domination of the most powerful.

John Stuart Mill, 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 implies the right to exercise civil rights, such as standing for office.

Alexis de Tocqueville, in his work, Democracy in America, was the first to coin the terms soft tyranny and mutual liberty.^[1] Likewise, John Stuart Mill offered insight into the notions of soft tyranny and mutual liberty with his harm principle.^[2] Overall, it is important to understand these concepts when discussing liberty since they all represent little pieces of the greater puzzle known as freedom. In a philosophical sense, morality must supersede tyranny in any legitimate form of government. Otherwise, people are left with a societal system rooted in backwardness, disorder, and regression.

David Kelley's work Liberty and Property states that liberty is the freedom to own property. While liberty means basic rights to free will, the "expression of an idea requires a physical medium" such as books, bullhorns or printing presses. A government that allows freedom of thought without freedom of property is not expressing the right to liberty.

Positive liberty is an idea that was first expressed and analyzed as a separate conception of liberty by John Stuart Mill but most notably described by Isaiah Berlin. It refers to the opportunity and ability to act and fulfill one's own potential, as opposed to negative liberty, which refers to freedom from coercion.

Positive liberty is often described as freedom to achieve certain ends, while negative liberty is described as from external coercion. The idea of positive liberty is often emphasized by those on the left-wing of the political spectrum, whereas negative liberty is most important for those who lean towards libertarianism. However, not all on either the left or right would accept the positive/negative liberty distinction as genuine or significant.

Among the right-wing, some conservatives also embrace some forms of positive liberty. For example, Puritans such as Cotton Mather often referred to liberty in their writings, but focused on the liberty from sin (e.g. sexual urges) even at the expense of liberty from the government. Many anarchists, and others considered to be on the left-wing, see the two concepts of positive and negative liberty as interdependent and thus inseparable.

While he described the concept of positive liberty, Isaiah Berlin was deeply suspicious of it. He argued that the pursuit of positive liberty could lead to a situation where the state forced upon people a certain way of life, because the state judged that it was the most rational course of action, and therefore, was what a person should desire, whether or not people actually did desire it.

Defenders of ''positive liberty'' say that there is no need for it to have such totalitarian undertones, and that there is a great difference between a government providing positive liberty to its citizens and a government presuming to make their decisions for them. For example, they argue that any democratic government upholding positive liberty would not suffer from the problems Berlin described, because such a government would not be in a position to ignore the wishes of people or societies. Also, many on the left see positive liberty as guaranteeing equal rights to certain things like education and employment, and an important defense against discrimination — here, positive liberty could be the governmental demand that (for example) the sex of an applicant be ignored when a firm hires a new employee.

The philosophical concept of negative liberty refers to an individual's liberty from being subjected to the authority of others. In this negative sense, one is considered free to the extent to which no person interferes with his or her activity. According to Thomas Hobbes, for example, "a free man is he that... is not hindered to do what he hath the will to do."

The distinction between negative liberty and positive liberty was drawn by Isaiah Berlin in his lecture entitled "Two Concepts of Liberty." According to Berlin, this distinction is deeply embedded in the political tradition: the notion of negative liberty being associated most strongly with the classical British political philosophers (e.g. Locke, Hobbes and Smith) and positive liberty with continental European thinkers such as Hegel, Rousseau, Herder, and Marx.

The concept of negative liberty has several noteworthy aspects. First, negative liberty defines a realm or "zone" of freedom (in the "silence of law"). In Berlin's words, "liberty in the negative sense involves an answer to the question 'What is the area within which the subject -- a person or group of persons -- is or should be left to do or be what he is able to do or be, without interference by other persons." Some philosophers have disagreed on the extent of this realm while accepting the main point that liberty defines that realm in which one may act unobstructed by others. Second, the restriction (on the freedom to act) implicit in negative liberty is imposed by a person or persons and not due to causes such as nature, lack, or incapacity. Helvetius expresses this point clearly: "The free man is the man who is not in irons, nor imprisoned in a gaol (jail), nor terrorized like a slave by the fear of punishment... it is not lack of freedom not to fly like an eagle or swim like a whale."

The dichotomy of positive and negative liberty is considered specious by political philosophers in traditions such as socialism, social democracy, libertarian socialism, and Marxism. Some of them argue that positive and negative liberty are indistinguishable in practice, while others claim that one kind of liberty cannot exist independently of the other. A common argument is that the preservation of negative liberty requires positive action on the part of the government or society to prevent some individuals from taking away the liberty of others.

In 1967, Gerald MacCallum argued that proponents of positive and negative liberty converge on a single definition of liberty, but simply have different approaches in establishing it. According to McCallum, freedom is a triadic relationship: X is an agent, Y is an obstacle, and Z is an action or state, where X is free to go from Y to do or become Z. In this way, rather than defining liberty in terms of two separate paradigms, positive and negative liberty, he defined liberty as a single, complete formula.

The first known use of the word freedom in a political context dates back to the 24th century BC, in a text describing the restoration of social and economic liberty in Lagash, a Sumerian city-state. Urukagina, the king of Lagash, established the first known legal code to protect citizens from the rich and powerful. Known as a great reformer, Urukagina established laws that forbade compelling the sale of property and required the charges against the accused to be stated before any man accused of a crime could be punished. This is the first known example of any form of due process in the history of humanity.

Like Urukagina, most ancient freedoms focused on negative liberty, protecting the less fortunate from harassment or imposition. Other ancient legal codes, such as the Code of Hammurabi, similarly forbade compulsion in economic matters, like the sale of land, and made it clear that when a rich man murders a poor one, it is still murder. Still, these codes relied on a certain virtuousness of kings and ministers, which was far from reliable.

Roman law also embraced certain limited forms of liberty, even under the rule of the Roman Emperors. However, these liberties were accorded only to Roman citizens. Still, the Roman citizen enjoyed a combination of positive liberty (the right to freely enter contracts, the right to a legal marriage) and negative liberty (the right to a trial, a right to appeal and the right to not be tortured). Many of the liberties enjoyed under Roman law endured through the Middle Ages, but were enjoyed solely by the nobility, never by the common man. The idea of unalienable and universal liberties had to wait until the Age of Enlightenment.

The social contract theory, invented by Hobbes, Locke and Rousseau, was among the first one to provide a political classification of rights, in particular through the notion of sovereignty and of natural rights. The thinkers of the Enlightenment reasoned the assertion that law governed both heavenly and human affairs, and that law gave the king his power, rather than the king's power giving force to law. The divine right of kings was thus opposed to the sovereign's unchecked auctoritas. This conception of law would find its culmination in Montesquieu's thought. The conception of law as a relationship between individuals, rather than families, came to the fore, and with it the increasing focus on individual liberty as a fundamental reality, given by "Nature and Nature's God," which, in the ideal state, would be as expansive as possible. The Enlightenment created then, among other ideas, liberty: that is, of a free individual being most free within the context of a state which provides stability of the laws. Later, more radical philosophies such as socialism articulated themselves in the course of the French Revolution and in the 19th century.

The modern conceptions of democracy, whether representative democracies or other types of democracies (including the past communist "popular democracies"), are all found on the Rousseauist idea of popular sovereignty ^{[original research?]}. However, liberalism distinguishes itself from socialism and communism in that it advocates for a form of representative democracy, while socialism claims to work for a direct democracy (although, in the case of communism, this was supposed to be achieved through a period of dictatorship of the proletariat, a concept which was instrumentalized during the Cold War to legitimate authoritarian regimes).

Liberalism is a political current embracing several historical and present-day ideologies that claim defence of individual liberty as the purpose of government. Two main strands are apparent, although both are founded on an individualist ideology. In continental Europe the term usually refers to economic liberalism, that is the right of individual to contract, trade and operate in a market free of constraint. In the United States it often refers to social liberalism, including the right to dissent from orthodox tenets or established authorities in political or religious matters. Both are core political issues, and highly contentious.

A school of thought popular among US libertarians holds that there is no tenable distinction between the two sorts of liberty -- that they are, indeed, one and the same, to be protected (or opposed) together. In the context of U.S. constitutional law, for example, they point out that the constitution twice lists "life, liberty, and property" without making any distinctions within that troika.

Anarcho-Individualists, such as Max Stirner, demanded the utmost respect for the liberty of the individual. From a very similar perspective from North America, primitivists like John Zerzan proclaimed that civilization not just the state (as in socialist thought) would need to be abolished to foster liberty. Some in the US see protecting the ideal of liberty as a conservative policy, because this would conform to the spirit of individual liberty that they consider is at the heart of the American constitution. Some think liberty is almost synonymous with democracy, at least in one sense of that word, while others see conflicts or even opposition between the two concepts.

• Freedom (political)
• Freedom (philosophy)
• Gratis versus Libre
• John Stuart Mill's On Liberty
• Liberté, égalité, fraternité

Wikiquote has quotations related to Liberty.

• Stanford Encyclopedia of Philosophy entry on negative and positive liberty
• The Future of Freedom
• The Rights of the Colonists University of Chicago