John Locke

Introduction

John Locke (1632–1704) transformed legal and political philosophy through his theory of natural rights, limited government, and the right of revolution. His Two Treatises of Government (1689) provided the philosophical justification for the Glorious Revolution and profoundly influenced the American Declaration of Independence and the U.S. Constitution. Where Hobbes used the social contract to justify absolutism, Locke employed it to ground constitutional limits on state power. Locke’s Letter Concerning Toleration (1689) also established principles of religious freedom that shaped modern constitutional protections of conscience. His Essay Concerning Human Understanding (1690) provided the epistemological foundations of his political theory.

The State of Nature and Natural Law

Locke’s state of nature differs markedly from Hobbes’s. It is “a state of perfect freedom to order their actions and dispose of their possessions and persons as they think fit, within the bounds of the law of nature.” It is also a state of equality, where no one has jurisdiction over another. The law of nature—accessible through reason—teaches that “being all equal and independent, no one ought to harm another in his life, health, liberty, or possessions.” Unlike Hobbes, Locke believed the state of nature is governed by a moral law that obliges even in the absence of government. However, enforcement is insecure because each individual must judge and punish violations themselves, leading to partiality, confusion, and conflict that make civil government necessary.

Natural Rights: Life, Liberty, and Property

Locke grounded rights in the natural law. Each person has a right to life, which no government may arbitrarily take; individuals cannot enslave themselves, and government cannot take life without due process. Liberty consists in freedom from arbitrary domination, not merely the absence of physical restraint—it requires government by consent and law. Property arises from labor: “Whatsoever then he removes out of the state that nature hath provided and left it in, he hath mixed his labour with, and joined to it something that is his own, and thereby makes it his property.” The right to property is therefore pre-political and cannot be abolished by government, though it may be regulated. Locke’s labor theory of value argues that labor creates the vast majority of value in property and therefore grounds the moral claim to ownership. This theory remains influential in intellectual property, land law, and debates about distributive justice.

The Social Contract and Limited Government

Individuals consent to form civil society to remedy the inconveniences of the state of nature—particularly the lack of established, known laws, an impartial judge, and executive power to enforce judgments. The social contract creates a government with fiduciary character: its powers are held in trust for the people. Government must rule through “promulgated established laws, not by extemporary decrees.” An independent judiciary must apply those laws. Crucially, the legislature is supreme but limited: it cannot take property without consent, legislate arbitrarily, or transfer its lawmaking power. Locke also argued for a separation of legislative and executive powers, with the executive subordinate to the legislature but possessing prerogative power to act for the public good in emergencies when the legislature cannot meet.

The Right of Revolution

Locke’s most radical contribution is the right of revolution. When government acts contrary to its trust—when the executive employs force without law, when the legislature attempts to enslave the people, or when either branch systematically violates rights—the people may dissolve the government and establish a new one. This right is not anarchic; it operates only against a “long train of abuses.” The appeal to heaven—the people’s ultimate judgment—is the final check against tyranny. Locke’s careful articulation of the conditions for legitimate revolution provided the intellectual framework for the Glorious Revolution of 1688 and, later, the American Revolution of 1776. Thomas Jefferson’s Declaration of Independence echoes Locke’s logic, enumerating grievances against George III and asserting the right of the people to alter or abolish destructive government.

Locke and Religious Toleration

Locke’s Letter Concerning Toleration argued for the separation of church and state and the protection of religious freedom. He distinguished the civil interests that government protects (life, liberty, property) from the salvation of souls, which is a matter of individual conscience beyond governmental competence. The care of souls is not committed to the civil magistrate because: true religion requires inward conviction that force cannot produce; the power of the magistrate extends only to outward goods; and the loss of eternal life is far greater than any civil penalty. Locke excluded Catholics from toleration on grounds of their allegiance to a foreign sovereign (the Pope) and atheists on grounds that promises and oaths require belief in divine sanctions. Despite these limitations, Locke’s arguments for toleration established the liberal principle that the state should not coerce religious belief.

Locke’s Theory of Property and Labor

Locke’s labor theory of property has profound implications for legal thought. By grounding property rights in the labor that transforms common resources into private goods, Locke provided a moral foundation for ownership that competing theories—state concession, first possession, or utilitarian efficiency—struggle to match. The labor theory raises questions about the limits of acquisition: Locke’s “sufficiency proviso” required that enough and as good be left for others, and his “spoilage proviso” prohibited taking more than could be used. These limitations have been debated by libertarians (who read Locke as justifying absolute property rights), egalitarians (who emphasize the provisos), and scholars of intellectual property (who apply Lockean reasoning to patents and copyrights). The labor theory remains central to property theory.

Legacy

Locke’s ideas directly shaped the American Founding. Thomas Jefferson’s Declaration of Independence echoes Locke’s language of “life, liberty, and the pursuit of happiness.” The U.S. Constitution’s separation of powers, its protection of property, and its recognition of unalienable rights reflect Lockean constitutionalism. Locke’s influence extends also to modern human rights law, property theory, and the liberal tradition generally. Salus populi suprema lex—the welfare of the people is the supreme law—captures the spirit of his enterprise. Locke’s conception of natural rights, limited government, and the right of revolution remains the bedrock of constitutional democracy worldwide.