Philosophy 160
Introduction to Ethics

Handout 11 - Noonan

Noonan's Main Thesis
Abortion is morally wrong unless it is required to save the life of the mother.

Noonan's Main Argument (featuring "The Injury Principle")

"The commandment could be put in humanistic as well as theological terms: do not injure your fellow man without reasons. In these terms, once the humanity of the fetus is perceived, abortion is never right except in self-defense" (Noonan, second to last paragraph).

1. It is morally wrong to injure another person unless it is done to save a life.
2. A fetus is a person.
3. Therefore, it is morally wrong to injure a fetus unless it is done to save a life.
4. If it is morally wrong to injure a fetus unless it is done to save a life, then abortion is morally wrong unless it is required to save the life of the mother.
5. Therefore, abortion is morally wrong unless it is required to save the life of the mother.

Counterexample to The Injury Principle (premise 1): The Case of the Knife-Wielding Thief

Another Anti-Abortion Argument (featuring "The Killing Principle")

1. It is morally wrong to kill another person unless it is done to save a life.
2. A fetus is a person.
3. Therefore, it is morally wrong to kill a fetus unless it is done to save a life.
4. If it is morally wrong to kill a fetus unless it is done to save a life, then abortion is morally wrong unless it is required to save the life of the mother.
5. Therefore, abortion is morally wrong unless it is required to save the life of the mother.

Possible Counterexample to The Killing Principle (premise 1): The Case of the Knife-Wielding Rapist

Third Anti-Abortion Argument (featuring "The Killing-the-Innocent Principle")

1. It is morally wrong to kill an innocent person unless it is done to save a life.
2. A fetus is an innocent person.
3. Therefore, it is morally wrong to kill a fetus unless it is done to save a life.
4. If it is morally wrong to kill a fetus unless it is done to save a life, then abortion is morally wrong unless it is required to save the life of the mother.
5. Therefore, abortion is morally wrong unless it is required to save the life of the mother.

Two Concepts of Personhood

The word 'person' is ambiguous (that is, it, has at least two distinct meanings (like the word 'bank')).

'Person' in the Biological Sense: a member of Homo sapiens

examples: each of us, human corpses

'Person' in the Psychological Sense: a creature with a psychology similar to ours (it is conscious, is self-conscious, engages in reasoning, in rational deliberation, in self-motivated activity, has the capacity to communicate, devises and carries out plans)

examples: each of us, C3P0 (from Star Wars), Chewbacca (from Star Wars), Data (from Star Trek), any intelligent enough alien or robot.

A Key Point: It is the concept of a person in the psychological sense that plays a role in moral principles (such as the principles in the arguments above).

Third Anti-Abortion Argument (Disambiguated)

1. It is morally wrong to kill an innocent person (in the psychological sense) unless it is done to save a life.
2. A fetus is an innocent person (in the biological sense).
3. Therefore, it is morally wrong to kill a fetus unless it is done to save a life.
4. If it is morally wrong to kill a fetus unless it is done to save a life, then abortion is morally wrong unless it is required to save the life of the mother.
5. Therefore, abortion is morally wrong unless it is required to save the life of the mother.

The Fallacy of Equivocation

It therefore turns out that Noonan's argument (or the more sophisticated one we call the 'Third Anti-Abortion Argument') commits the "fallacy of equivocation."

An argument commits the fallacy of equivocation when it uses the same word to mean two different things in two different premises.

The following argument is an example of an argument that commits the fallacy of equivocation:

1. Money is kept in banks.
2. Banks are sides of rivers.
3. Therefore, money is kept in sides of rivers.

Although an argument that commits the fallacy of equivocation appears to be valid, it is actually invalid.  Thus, one can accept the premises without having to accept the conclusion.