PHIL 2030: Introduction to Ethics
Dr. Robert Lane
Lecture Notes: Thursday February 13, 2014


After you have completed the reading for Thursday February 13 (RTD ch.12: Judith Jarvis Thomson, “A Defense of Abortion,” please read and study the following set of notes. We will not be discussing them in detail during class, but you will be responsible for this information.


There is no further reading assignment for Tuesday February 18. When you come to class on that day, you should have already read RTD ch.11 (by Marquis) and RTD ch.12 (by Thomson).


At the start of class on Tuesday 2/18, we WILL have a quiz on the articles by Marquis and Thomson and over the lecture notes for Tues 2/11 and Thurs 2/13.



Continuing our examination of Don Marquis’ “FLO” Argument against abortion…


1.      If killing a being will deprive it of an FLO, then it is prima facie morally wrong to kill that being.

2.      Killing a fetus deprives it of an FLO.

3.      Therefore, it is prima facie morally wrong to kill fetuses. [supposed to follow from 1 and 2]

4.      In the vast majority of abortions, there are no other moral considerations that trump the prima facie obligation not to kill a fetus.

5.      Therefore, the vast majority of abortions are immoral. [supposed to follow from 3 and 4]



A note about Marquis’s use of the word “fetus”: Sometimes the word “fetus” is used in a narrow sense, to refer only to pre-birth humans during and after the ninth week of pregnancy. But Marquis is using the word “fetus” in a broader sense, to mean a pre-birth human from around day 14 of pregnancy to birth.


Why around day 14? One reason may be that by that time, twinning (the division of a single pre-birth human into two) is no longer possible. Although he doesn’t say so explicitly, it seems that Marquis intends his account to apply only after the embryo can no longer split to become twins.[1]


Marquis is arguing that abortion is prima facie immoral:

·         The conclusion of his argument leaves room for special cases in which the obligation not to kill a fetus might be overridden (e.g., cases in which the mother’s life would be threatened by bringing the fetus to term).

·         But the fact that there are such special cases does not mean that abortion, in general, is morally acceptable. Marquis believes that in the vast majority of cases, abortion is morally wrong.



·         Is the first step of the argument (from 1 and 2 to 3) valid? [yes]

·         Is the second step (from 3 and 4 to 5) valid? [yes]

·         Are the premises true? [1, 2 and 4?] – I am leaving this an open question… you should form your own opinions about whether each of these premises is true.



[5.1.3.] The Objection from Mother’s Rights.


This objection to Marquis’s argument says that, although the argument is valid, and although premises 1 and 2 may be true, the argument is unsound because premise 4 is false. Here’s why…


The abortion issue does not concern just the interests of the fetus.


It also concerns a person’s basic moral right to control what happens in and to his or her body.


This includes a woman’s basic moral right to choose whether or not to continue a pregnancy.


So Marquis may be right that a woman has a prima facie obligation not to deprive her fetus of an FLO. But even if this is correct, that obligation is outweighed by her right to control her own body. So while it may be true that a woman has a prima facie moral duty not to end a pregnancy, it is false that in the vast majority of cases, there is no other moral consideration that outweighs that duty. Premise 4 is false.



[] Reply to the Objection from Mother’s Rights.


According to Marquis, “The loss of one’s life is almost the greatest misfortune that can happen to one. Presumably abortion could be justified in some circumstances, only if the loss consequent on failing to abort would be at least as great.” (RTD 87) This suggests the following defense of premise 4 against the Objection from Mother’s Rights…


In order for abortion to be morally justified by the right of a mother to choose, the loss that the mother would suffer by continuing the pregnancy (loss of time, energy, money, comfort, etc.) would have to outweigh the loss suffered by the fetus if the pregnancy is aborted. But the loss suffered by the fetus is the greatest loss that a being can suffer: the loss of an FLO. And this loss seems to outweigh the loss of time, energy, etc. suffered by the mother.


So, according to this reply to the objection from mother’s rights, the right of the mother to choose does not outweigh the loss suffered by the fetus. So the Objection from Mother’s Rights does not show that premise 4 is false.



[5.2.] Judith Thomson’s Defense of Abortion.


Judith Jarvis Thomson is a philosophy professor at MIT.[2]


Her paper, “A Defense of Abortion,” was published in 1971, 18 years before Marquis published his pro-life argument. It is one of the most widely reprinted and discussed papers in ethics.



[5.2.1.] Would Fetal Personhood Imply that Abortion is Immoral?


Thompson begins by granting that from the moment of conception, a fetus is a person with a right to life.

·         Thomson herself does not believe this. She says that “A newly fertilized ovum, a newly implanted clump of cells, is no more a person than an acorn is an oak tree.” (RTD 92) She is merely granting this point for the sake of argument.

·         She grants this point because she wants to examine what follows from it. In particular, she wants to see whether the claim that a fetus is a person with a right to life implies that abortion is immoral. She notes that pro-lifers spend most of their time trying to argue that a fetus is a person without then showing that this implies that abortion is wrong:


Opponents of abortion commonly spend most of their time establishing that the fetus is a person and hardly any time explaining the step from there to the impermissibility of abortion. Perhaps they think the step too simple and obvious to require much comment ... I suggest that the step [from the claim that a fetus is a person to the claim that abortion is immoral] is neither easy nor obvious, that it calls for closer examination than it is commonly given, and that when we do give it this closer examination we shall feel inclined to reject it. (RTD 88-89)


In other words, many pro-choicers spend their time trying to argue that the first premise of this argument is true:


1.      A fetus is a person with a right to life.

2.      Therefore, abortion is immoral.


without trying to show that the argument is valid (i.e., that the conclusion really does follow from the premise).


So, in summary, she begins by asking this question: would the fact that a fetus is a person imply that abortion is immoral?



[5.2.2.] The Violinist Thought-Experiment.[3]


She begins her attempt to answer that question with the Violinist Thought-Experiment:


Suppose that you wake up one morning and find yourself in a hospital bed, connected by many tubes to another person, who is unconscious. The director of the hospital is there and explains to you that the person sharing your bed is a world-famous violinist. The violinist has a kidney disease and requires the use of someone else’s kidneys to extract toxins from his blood.


So how did you come to be connected to the violinist? The Society of Music Lovers (SML) examined all available medical records and determined that your kidneys are uniquely capable of saving the violinist’s life. So they kidnapped you and connected you in the appropriate ways to the violinist. The hospital director says that she never would have allowed this herself, but the SML people did it on their own and then dropped you off at the hospital. So far as the director is concerned, you are free to disconnect yourself from the violinist and go, but if you do so, the violinist will die. “How long will I have to stay connected to him, in order for him to live?” you ask.


Suppose the doctor says: nine months. Would you then think that it would be wrong to disconnect from the violinist? What if the doctor says nine years? Would it still be wrong to disconnect? What if the doctor says the rest of your life?


At this point, Thomson reasons as follows:


1.      If the violinist’s right to life always outweighs your right to determine what happens in your body, then it is always immoral to disconnect, no matter how long the violinist needs to use your body.

2.      But it is not always immoral to disconnect (e.g., your entire life, it would be morally permissible to disconnect).

3.      So, the violinist’s right to life does not always outweigh your right to determine what happens in your body.


This is a modus tollens argument, so it is valid (if the premises were true, the conclusion would have to be true … but are the premises true?


The notes on Thomson will continue on Tuesday February 18.



Stopping point for Thursday February 13. No new reading for next time; we will finish our coverage of Thomson’s article.


At the beginning of class on Tuesday February 18, we will DEFINITELY have a pop quiz. It will cover:

·         the lecture notes for Tues 2/11 and Thurs 2/13

·         RTD ch.11 (Marquis, “Why Abortion is Immoral”

·         RTD ch.12 (Thomson, “A Defense of Abortion”



[1] I believe this is what he has in mind when he says that “morally permissible abortions will be rare indeed unless, perhaps, they occur so early in pregnancy that a fetus is not yet definitely an individual.” (RTD 91; in original article on p.194). He mentions the 14 day point in a later statement of his FLO argument: he describes his position as being that abortion is wrong, except perhaps in rare instances, e.g. “abortion during the first fourteen days after conception when there is an argument that the fetus is not definitely an individual.” “An Argument that Abortion is Wrong,” in Ethics in Practice, ed. Hugh LaFollette. Cambridge, MA: Blackwell, 1997, 91-102, p.91. [So far as I have been able to discover from embryology texts, twinning can occur only as late as day nine, and at that point the twins are at risk of being conjoined. (Scott Gilbert et al., Bioethics and the New Embryology, p.16)] See also the following, from a revised version of “Why Abortion is Immoral” which appears in Morality in Practice, 6th ed., ed. James Sterba, pp.125-9: “This essay will neglect a discussion of whether there are any such compelling considerations and what they are. Plainly there are strong candidates: abortion before implantation . . .”


[3] For more on thought experiments, see James Robert Brown and Yiftach Fehige, “Thought Experiments,” The Stanford Encyclopedia of Philosophy (Fall 2011 Edition), Edward N. Zalta (ed.), URL = <>.

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