Perhaps you heard the Church of England is mulling its definition of woman. A leading figure in the C of E, Rt. Rev. Robert Innes, reports that “There is no official definition, which reflects the fact that until fairly recently definitions of this kind were thought to be self-evident, as reflected in the marriage liturgy.” In light of that, he cautioned, “additional care” is in order.

Crossing the pond, it’s doubtful that such care will be forthcoming from the newest member of our Supreme Court. At her confirmation hearing, when asked to define woman, now Justice Ketanji Brown Jackson told Sen. Marsha Blackburn “I can’t.”

Nonetheless, SCOTUS is our final arbiter on the legal definition of woman. And this much is certain: every woman is a person. But now comes the question of just what a person is! Again, the Court is the arbiter of the legal definition of person. Well, then, it turns out that a corporation is a legal person. This determination, however, does not sit well with critics of the corporate sector. There’s something to be said for their complaint. Everyone knows, after all, that no corporation is a real person.

To its credit, in the Dobbs ruling, the Court showed some interest in what a person really is. Justice Alito, with regard to viability as a line for State interest in the preborn, notes that “This arbitrary line has not found much support among philosophers and ethicists who have attempted to justify a right to abortion.” What line would make sense? “Some have argued,” he continues, “that a fetus should not be entitled to legal protection until it acquires the characteristics that they regard as defining what it means to be a ‘person.’” At this point, Alito introduces a trio of our contemporaries. Peter Singer, Mary Anne Warren, and Michael Tooley have long contended that a pre-born human being is not a person. No such human being, they argue, has the “essential attributes of ‘personhood’ [namely] sentience, self-awareness, the ability to reason, or some combination thereof.”

Justice Alito, however, is not impressed. “By this logic,” he remarks, “it would be an open question whether even born individuals, including young children or those afflicted with certain developmental or medical conditions, merit protection as ‘persons.’” Definitional gerrymandering doesn’t work.

St. Thomas Aquinas, following Boethius, defines a person as an individual substance that is a member of a rational kind. Each and every human being is an individual. No human being is an accidental quality of something; rather each is a substance. Every human being is rational in nature, even though that rationality might be largely potential or in some way compromised. So it is that every pre-born human being is a person.

Where does this definition have its start? From our experience. We experience each other as rational in that we deliberate and act on the basis of our deliberations, however imperfect they may be. We experience the generational coming to be of human beings. We recognize that it is our treating them as persons that enables them to develop as persons.

To the extent that our legal system cannot recognize that all human beings are persons, and that this is a truth about humanity, our legal system is deeply flawed. We have suffered too long from that flaw. We can, and should, work to remedy it.

People quarrel, Chesterton quips, because they don’t know how to argue. Indeed, people fly into rages because they don’t know how to argue. But we can’t construct arguments without defining our terms. Let’s get it right.