What is a "Person"?

A definition for moral philosophy.

Pro-Lifers don’t see why anyone would believe in a humanhood vs. personhood distinction. They think that humanhood and personhood are one and the same. But that’s a hard position to defend. If we met space aliens who were intelligent to have thoughts and articulate their ideas and make plans for the future just like us, I think most people would say they were people. All of our moral commandments like “don’t murder people” would apply to the aliens just as much as to humans. On the other side of things, there are some things that are human, but not persons. Every sperm and egg cell has human DNA but a sperm cell is not a person. It’s not clear why a fertilized egg would be a person. The reason can’t be that a fertilized egg has a unique genetic code, because when identical twins form, there are two separate embryos with the same DNA, so neither entity has a unique genetic code.

There are also fully physically developed human adults who stretch the boundaries of the personhood concept. There are adults who are so severely mentally retarded that they cannot speak. Some cannot even move or eat without assistance. They clearly do not have the kind of mental life that you and I and other non-retarded humans have. I don’t think that’s a person.

Here is my definition of “person”:

• A person is a conscious being who has or will develop the ability to conceive of their life as a whole.

The definition includes:

• All regular humans, including most people with Down Syndrome and other forms of mild mental retardation are people by this definition.

• Intelligent space aliens would be people.

• A fetus of 24 20 weeks or older. Around 24 20 weeks, the fetus gains consciousness. At that point its level of intelligence is probably on the order of a small animal, but it will naturally develop to the point that he or she will be able to have a concept of his or her own life as a whole.

It does not include:

• Profoundly mentally retarded humans are not people. (a very small number of humans)

• Animals like rabbits, lions, dogs, mice and deer are not people (though I’m less sure about chimpanzees and dolphins). Rabbits, dogs and deer are conscious, i.e. they can have conscious experiences, but I don’t think that they have any conception of their life as a whole. I think the experience of a deer is just one day after the other. They can feel pleasure, pain and fear, but the deer is always in the moment. It doesn’t have any conception of what it would like its life as a whole to be.

• Embryos and early fetuses which have not yet “woken up” and started to have conscious experience. Before they have had their first conscious experience, there is no “there” there. There is no mind. The time at which the fetus makes its first movements is called “quickening” and in the middle ages quickening was the point at which the catholic church held that the fetus had been endowed with a soul.

This definition of “person” makes sense of the rights of people. All conscious beings, including animals, have the right to not be tortured. But people have additional rights, such as the right to own property and the right to not be murdered painlessly. If people by definition have the ability to conceive of their lives as a whole, then people can have preferences about how their lives go, and a person can be harmed by being murdered because that conflicts with the way they would like their life to go - even if they are murdered painlessly in their sleep. By contrast, a deer which always lives in the moment does not have any preferences about its life as a whole because it has no concept of its life as a whole. So the deer has none of its preferences violated when it is killed painlessly in its sleep.

Unlike animals or profoundly retarded humans who always live in the moment, people can make plans for the future, and they can acquire property and build things to bring their plans to fruition.

Key Takeaway: To be a person a being must meet two criteria:

1. The being must be conscious

2. The being must be able to conceive of its life as a whole, or it must be on the course to naturally develop that ability.