Definition
Natural rights carries two distinct meanings in legal usage — one philosophical and constitutional, the other technical and property-specific. Both appear in the historical dictionaries, and conflating them is a persistent research hazard.
1. Philosophical and constitutional sense. Rights considered inherent to human beings by virtue of their nature or reason, existing independently of and prior to any government, positive law, or social compact. In this sense, natural rights are not granted by constitutions or statutes — they are recognized or secured by them. The canonical examples are rights to life, liberty, and property (or, in the Lockean formulation that influenced American constitutionalism, life, liberty, and estate). This is the sense invoked in Enlightenment political philosophy, in founding-era American legal and political writing, and in constitutional interpretation debates about unenumerated rights.
2. Property law sense. A distinct and narrower technical meaning: rights that attach to land ownership as a matter of common law, without need of grant, prescription, or any separate legal instrument. They are incidents of ownership itself — rights the landowner holds by virtue of holding the land. The most significant example is the right to lateral and subjacent support: a landowner's right to have adjoining land provide natural support to their parcel. This right exists as a natural right in the technical property sense, meaning it arises automatically and does not require an easement or other recorded interest. It is distinguished from easements, which are created or acquired; natural rights in this sense simply exist as background entitlements of ownership.
---
Common Language
Wiktionary: Plural of natural right — rights that a person has by virtue of being human, not dependent on any government.
Webster's 1913: "Rights possessed by man in the state of nature — as, the right to life, liberty, and the pursuit of happiness." Treated as self-evidently belonging to moral and political discourse.
The common English meaning captures only the philosophical sense. The property-law technical meaning — rights incident to land ownership, particularly support rights — has no counterpart in ordinary usage and is entirely invisible to non-specialist readers. A researcher encountering "natural rights" in a property law treatise or real property decision may assume the philosophical register when the author means something far more specific and doctrinal.
---
Common Confusion
The two definitions above are not merely different emphases on the same concept — they are operationally distinct in research contexts. The philosophical sense appears in constitutional law, jurisprudence, political theory, and founding-era sources. The property law sense appears in real property treatises, landlord-tenant materials, and cases involving excavation, grading, subsidence, and support obligations. A source using "natural right" in a property dispute is almost certainly not invoking Locke; it is invoking the common law doctrine that support rights need not be separately created. Bouvier's entry makes this split explicit, but many researchers encounter only one sense or the other and do not recognize the term is doing double duty.
---
Why It Matters in Research
The philosophical sense of natural rights is foundational to American constitutional history and has undergone significant transformation in legal usage. Founding-era and early republic sources treat natural rights as a live, operative category — a basis for legal argument and constitutional interpretation, not merely political philosophy. Through the nineteenth and into the early twentieth century, the term migrates increasingly toward academic jurisprudence and away from routine legal argument, though it resurfaces forcefully in constitutional debates about unenumerated rights, substantive due process, and the Ninth Amendment. Researchers working in constitutional history must be alert to this trajectory: the term carries more direct legal weight in 1790 than in 1890, and more contested weight again in the late twentieth century.
For property law researchers, the technical sense creates a different navigational problem. Historical property treatises — including those in the Law Mind corpus — use "natural right" as a term of art without always flagging that they are using it technically. When Bouvier references "rights which pass with the property in the land as incidents to the land itself," he is describing a specific doctrinal category, not a philosophical claim. The Law Mind Property Law Encyclopedia's treatment of lateral and subjacent support is the right destination for this strand of research. Researchers who arrive at that material via a constitutional law search path may be confused about why "natural rights" appears in an excavation context.
The intellectual property connection is also significant. Natural rights theory — particularly Lockean labor theory — is one of the canonical justifications for intellectual property protection, and it surfaces in both scholarly and judicial discussions of copyright and patent. The Law Mind IP Encyclopedia entry addresses this directly. This is the philosophical sense applied to a specific doctrinal domain, and it should not be confused with the property law technical sense.
Historical sources in the corpus will not consistently distinguish these usages. Context (property dispute vs. constitutional argument vs. IP theory) is the most reliable guide.
---
Historical Dictionary Support
Black's and Bouvier's together reveal the dual meaning but do not explicitly reconcile it. Black's gives the philosophical sense cleanly: rights "plainly assured by natural law," exemplified by life and personal liberty. This is the mainstream American legal dictionary treatment — natural rights as pre-political, foundational entitlements.
Bouvier's takes a notably different path. Rather than leading with the philosophical sense, Bouvier's entry (under Real Property Law) goes directly to the technical property meaning: rights incident to land ownership, distinguished from easements because they require no creation or acquisition. The citation to 6 App. Cas. 740 references an English case in the appellate courts — consistent with the support-rights doctrine's strong roots in English common law. Bouvier's treatment is valuable precisely because it foregrounds what Black's does not: that "natural rights" had a well-settled technical meaning in property practice that was quite separate from its philosophical career.
What neither historical dictionary provides is a synthesis or a disambiguation notice. Both entries are accurate in their respective domains; neither alerts the reader that the same phrase is doing two very different jobs in the legal literature. Modern researchers using these sources without context could easily read past the distinction entirely.
---
Jurisdictional Note
The philosophical sense of natural rights is most deeply embedded in American constitutional discourse, reflecting the Lockean and natural law influences on the founding generation. The property law technical sense — support rights as natural incidents of land ownership — derives from English common law and is recognized broadly in common law jurisdictions, though the precise scope of support rights (particularly for buildings and improvements vs. land in its natural state) varies by jurisdiction.
---
Encyclopedia Cross-Reference
Justifications for Intellectual Property — Utilitarian, Natural Rights, and Personality Theories (The Law Mind Intellectual Property Encyclopedia)
Lateral and Subjacent Support — Natural Right, Liability for Excavation (The Law Mind Property Law Encyclopedia)
---