Ethical Theory Spring 2021

How Do Rights Work?


Consequentialist theories such as utilitarianism hold that we should evaluate our behavior by looking solely at its consequences. Deontological theories do not. They hold that we should sometimes do things like respect others’ rights or perform our duties even if the consequences of doing so are worse than they otherwise would have been.

We started our section on consequentialist moral theories with a specific question: what obligations do affluent people have to help the needy? We’re doing something similar with deontological theories. Here, the question concerns whether there is a right to abortion.

Thomson’s Strategy

What is distinctive about Thomson’s strategy is that she thinks she has an argument for abortion rights that sidesteps the familiar disagreements about the point in human development at which fetuses become persons. She says that there would be a right to abortion even if fetuses were persons with the same right to life that any person has.

That’s the point of the famous violinist example. The violinist has the right to life but, Thomson thinks, you could unplug yourself from him even if he depended on being plugged into your body to stay alive. The lesson she draws from this is that the right to life does not give anyone a right to use another person’s body. She thinks it follows that fetuses do not have rights to use women’s bodies, even if they have the right to life.

More specifically, she thinks that the violinist example shows that there is something wrong with what she regards as a plausible sounding argument against abortion rights. Here is how that argument goes, assuming that fetuses are persons (Thomson 1971, 48).

  1. Suppose that fetuses are people and so have a right to life.
  2. Women have rights to decide what happens in and to their bodies.
  3. But the right to life outweighs that right.
  4. So fetuses may not be killed and there is no right to abortion.

But here is how most people think of the violinist case (Thomson 1971, 48–49).

  1. Suppose that violinists are people and so have a right to life.
  2. You have rights to decide what happens in and to your body.
  3. The right to life does not outweigh that right.
  4. So you have the right to unplug yourself from the violinist and the violinist may be killed.

Whether you think the argument is conclusive or not, you have to admit that it’s frightfully clever.

One thing to note is that Thomson is reasoning in a non-consequentialist way. If you think the more important interest should win, as a consequentialist does, you will probably think that the person connected to the violinist really should stay hooked up. And if you think that, you have no reason to follow her reasoning about abortion.

One thing I take away from Thomson is that people who believe in rights do not think like consequentialists.


I greatly admire this essay and I have never written anything nearly this good myself. That said, I think that it was probably a mistake to start off with what she calls the extreme view, namely, that abortion is wrong even to save the life of the pregnant woman. By doing it this way, she has to cover the same territory twice. I say this because, in my opinion, the real question is the one that is posed on page 55: what does the right to life give you a right to have? The extreme view gives one answer to that question and the less extreme views give other answers. By doing the extreme view first, she delays getting to the fundamental question and so has to repeat herself rather than moving forward.

In addition to this tactical point, I think she makes a substantive error here. Thomson describes the right to abortion in cases where the pregnant woman’s life is at risk as a right of self-defense. That’s not the way I would put it.

The right of self-defense is usually thought of as a right to use force against someone who is aggressively threatening you. Rights of self-defense do not usually cover competition for scarce resources. For instance, the people who are lower on the list for organ transplants are not allowed to kill those who are higher up in self-defense even though that would improve their chances of getting an organ. The cases involving abortion look to me like ones that involve competition for a scarce resource: two people want to use one body to stay alive.

I don’t think this hurts Thomson’s position. She has a pretty good argument that the pregnant woman should win this competition: it’s her body after all (Thomson 1971, 53). In fact, I think her presentation would be a lot simpler if she skipped self-defense entirely. She would not have to have separate discussions of what a person may do in defense of her own life and what a third party may do. Plus she could dispense with the weird example of the baby that will burst out of the house (Thomson 1971, 52–54).

The Main Question

The main question, as I said, is what the right to life gives someone the right to have. You could imagine a variety of answers.

  1. The right to whatever you need to live.
  2. The right not to have whatever you need to live taken away.
  3. The right not to be killed.
  4. The right not to be killed, provided you are innocent and not threatening others.
  5. The right not to be killed unjustly.

Thomson thinks the violinist example rules out the first four. That leaves number five. What does it mean to say that you may not be killed unjustly?

One thing it does not mean is that you have a right to morally decent behavior. That is the lesson of the chocolates. It is selfish not to share, but it is not unjust not to share. The chocolates belong to the selfish kid, after all, and we can do all sorts of morally indecent things with our property without being unjust to others.

We will end with Thomson considering an answer that seems a little closer to abortion. Suppose you gave someone the right to use a resource and that person needs that resource in order to live. If you took the resource away, you would treat that person unjustly. Indeed, you will kill that person unjustly.

This leads us to an objection that we will start with next time. In the violinist case, the person who is hooked up, namely “you,” is kidnapped. There is no question that you did not give the violinist the right to use your body. But most, though not all, pregnancies do not start with anything like kidnapping. So that looks like an important difference between the two cases. Since Thomson’s argument relies on showing that the two cases are similar, this threatens her position.

Thomson will try to approach this objection by asking whether the pregnant person can be accurately described as giving the fetus rights to use her body.

Key Points

These are the points from today’s class that should be familiar to you.

  1. The violinist example.
  2. The difference between how utilitarians would think about the right to life and how Thomson thinks about it.
  3. The difference between self-defense and competition for scarce resources.


Thomson, Judith Jarvis. 1971. “A Defense of Abortion.” Philosophy & Public Affairs 1 (1): 47–66.