Opinion of the Court
U. S., at 778; see also id., at 822–850 (Thomas, J., concurring in part and concurring in the judgment) (surveying history and reaching the same result under Fourteenth Amendment's Privileges or Immunities Clause).
Timbs and McDonald concerned the question whether the Fourteenth Amendment protects rights that are expressly set out in the Bill of Rights, and it would be anomalous if similar historical support were not required when a putative right is not mentioned anywhere in the Constitution. Thus, in Glucksberg, which held that the Due Process Clause does not confer a right to assisted suicide, the Court surveyed more than 700 years of "Anglo-American common law tradition," 521 U. S., at 710, and made clear that a fundamental right must be "objectively, deeply rooted in this Nation's history and tradition," id., at 720–721.
Historical inquiries of this nature are essential whenever we are asked to recognize a new component of the "liberty" protected by the Due Process Clause because the term "liberty" alone provides little guidance. "Liberty" is a capacious term. As Lincoln once said: "We all declare for Liberty; but in using the same word we do not all mean the same thing."[1] In a well-known essay, Isaiah Berlin reported that “[h]istorians of ideas” had catalogued more than 200 different senses in which the terms had been used.[2]
In interpreting what is meant by the Fourteenth Amendment's reference to "liberty," we must guard against the natural human tendency to confuse what that Amendment protects with our own ardent views about the liberty that Americans should enjoy. That is why the Court has long been "reluctant" to recognize rights that are not mentioned in the Constitution. Collins v. Harker Heights, 503 U. S. 115, 125 (1992). "Substantive due process has at times been
