Our contemporary concepts of human dignity are very much tied to the concept of personhood. “Person” is a nomen dignitatis, a term designating dignity, as Thomas Aquinas says. But how does that term relate to our human nature? And is every human being a person? A look at the history of the term will show us that it has a theological history, in which it was distinguished from that of a “nature.” But it is only in the modern age that this distinction, taken in a very different way, has led people to deny the dignity and personhood of every human being.