This article will respond to Princeton Professor, Peter Singer’s, case for infanticide.

Argument 1: Rationality and the Newborn Baby

Singer is a big proponent of abortion. The reason that he believes abortion is okay is that he does not think that the unborn child has a right to life. The reason he doesn’t think the unborn has a right to life is that he thinks the fetus is not a person. And the reason that the fetus is not a person is because he or she does not have the character traits of a person like rationality and self-awareness. (1) Singer writes, “the life of a fetus… is of no greater value than the life of a non-human animal at a similar level of rationality, self-awareness, capacity to feel and so on…” (2)

But then Singer goes on to argues that

“these arguments apply to the newborn baby as much as to the fetus. A week-old baby is not a rational and self-aware being, and there are many non-human animals whose rationality, self-awareness, capacity to feel and so on, exceed that of a human baby a week or a month old. If, for the reasons I have given, the fetus does not have the same claim to life as a person, it appears that the newborn baby does not either.” (3)

What Singer is doing here is drawing out the logical implications of the pro-choice argument.

Singer knows that there is a conflict between the view that human life is sacred and the one he is putting forward but he writes,

“I do not regard the conflict between the position I have taken and the widely accepted views about the sanctity of infant life as a ground for abandoning my position. In thinking about ethics, we should not hesitate to question ethical views that are almost universally accepted if we have reasons for thinking that they may not be as securely grounded as they appear to be.” (4)

For example, he recognizes that we may feel compelled to protect infants because they are cute looking. But he shows this kind of thinking is really absurd for it would be like saying that a baby seal has more of a right to life, with his big eyes and soft coat, than a baby gorilla. It’s also absurd to say that the newborn is so innocent and helpless, and that is why we should protect them. The unborn are equally innocent and helpless and yet pro-choicers have no problem with their lives being taken. Ultimately such arguments seem irrelevant to him. (5)



I agree with Singer that his arguments could easily be used to justify infanticide. I further agree that those who support abortion but decry infanticide as some great evil are being logically inconsistent. I am not saying that pro-choicers want infanticide to happen. But along with Paul Chamberlain, I would say it’s true that “There are times when the reasons we set out for doing one thing actually justify other actions that we have not yet begun to pursue and may not even be thinking of at the time.” (6)

Furthermore, were a law to be passed allowing infanticide, I think it would be downright hypocritical for abortion advocates to oppose it. A favorite pro-choice argument is “If you don’t like abortion, don’t have one.” Here I would say, “If you don’t like infanticide, don’t get your doctor to your kill your baby.”

What I really hope, though, is that the horror will push pro-choicers to reconsider their reasoning about abortion. After all, if a newborn can be a person with a right to life despite lacking self-awareness and rationality, then there’s no obvious reason why an unborn baby can’t be. Or if there is a reason, then it needs to be demonstrated on some other grounds.


First and foremost, there is a glaring weakness in Singer’s argument. For if it can be shown that abortion itself is morally impermissible, then the case for infanticide would topple like a house of cards.

Second, along with Christopher Kaczor, I disagree with the conclusion that abortion being legal shows the fetus does not have a right to life. (7) David Boonin has argued that being a person with a right to life still does not give you the right to use another person’s body without their consent. He uses the real-life case of David Shimp who refused to give his bone marrow to his cousin Robert McFall to make his point. (8) There are issues with this argument, too, but that’s a whole other discussion someone should write a series on.

Third, I disagree with Singer’s suggestion that a human being can be present even though a person is not. Singer’s idea is called body-self dualism, which as Kaczor explains, says “‘you’ are your aims, desires, awareness, and your body is not you. A human organism–not you– was born, and then” once it became self-aware and rational, “you began to exist.” (9) Many absurd conclusions follow from this. 1) None of us are human beings. 2) We were never born. 3) And no one has ever shown us love or affection because you can’t do that to desires and awareness. (10)

Fourth, Singer’s criteria actually work against his own goal of equality. In his essay, “All Animals Are Equal,” he states that “I am urging that we extend to other species the basic principle of equality that most of us recognize should be extended to all members of our own species.” (11) He points out that an implication of the principle of equality is that “our concern for others ought not depend on what they are like, or what abilities they possess…” (12) I can agree with him that all those forms of discrimination are bad. The fact that discrimination of any kind has led us to racism, sexism, and at times even speciesism, is a good reason to avoid it. However, there is a kind of discrimination that Singer is overlooking here: ageism.

You might accuse me of setting up a strawman of Singer’s argument and knocking it down here. After all, he didn’t deny that the unborn have a right to life because of their age. He denied they had a right to life based on their lack of rationality and self-awareness. But as Stephanie Gray writes, this is all tied to age and that can be shown to be the case by asking some “why” questions. First, we should ask why the newborn isn’t rational or self-aware. The answer is, her brain hasn’t developed enough yet. Next, we can ask why her brain hasn’t developed enough. The answer is that it hasn’t had time. (13) Gray concludes, “And time is reflected in our age. Why should personhood be grounded in age?” (14)

What Gray is defending here is called the substance view of persons. As Francis J. Beckwith explains, this view claims that

“a human being is intrinsically valuable because of the sort of thing it is and the human being remains that sort of thing as long as it exists. What sort of thing is it? The human being is a particular type of substance—a rational moral agent—that remains identical to itself as long as it exists, even if it is not presently exhibiting the functions, behaving in ways, or currently able to immediately exercise these activities that we typically attribute to active and mature rational moral agents.” (15)

So, the newborn is a human substance. She remains a human substance through every stage of development. In fact, it is the rational nature that all human substances possess that drives her to develop the kind of brain humans normally do. (16)

In his debate with Stephanie Gray, Singer denied that he was engaging in ageism. He also does not believe that adults who lack rationality and self-awareness, perhaps due to brain injury, are persons with a right to life. (17) I would agree that in that case, he is not engaging in ageism. Instead, he is devaluing humans based on their lack of ability to express the capacity for rationality and self-awareness. This type of discrimination is called ableism. (18) But that doesn’t change that what he is advocating for with newborns is a form of ageism.

Singer argues that the newborn’s life has no greater value than the life of non-human animals. Here, he has in mind chicken, cows, and pigs who he says “comes out well ahead of the fetus” and presumably the newborn in terms of “rationality, self-consciousness, awareness, autonomy, pleasure and pain and so on…” (19) Despite this, we have no problem eating them. On this basis, Singer suggests “that we accord the fetus no higher moral status than we give to a nonhuman animal at a similar level of rationality, self-consciousness, awareness, capacity to feel and so on.” (20)

But I would argue that the newborn is already valuable because she possesses a rational nature that goes beyond anything the pig, cow, or chicken has. While those animals may be exercising more rationality and self-awareness than her now, there will come a time when she surpasses them. That is because they have their own substances that include different stages of development. Those stages of development do not include growing the kind of brains that would make them rational like a human. (21)

I know Singer is worried about speciesism but grounding rights in kinds of nature does not guarantee that only humans can get a right to life this way. As Beckwith explains,  

“… if another species exists, whether in this world or in another (such as Klingons and Vulcans of Star Trek lore) which possesses a personal nature from the moment any of its individual members come into being, then pro-lifers would seek to have these creatures protected from unjustified homicide as well.” (22)

In fact, just recently I was at the Royal British Columbia Museum where they were holding an exhibit on Orca Whales. As it turns out, there is advocacy happening right now to have the personhood of orcas recognized so that their right to life may be recognized. Orcas come at least very close to the level of rationality and self-awareness that humans have. This recognition would prevent them from being hunted for meat and put into captivity. I would support such measures. (23) As Gray concludes, “Saying I believe we should make sure all humans are brought up to the level of how we treat most humans doesn’t necessarily mean I disagree with bringing animals up to that same level.” (24)

For these reasons, I do not find his arguments for infanticide based on rationality convincing.


In this article, I summarized some of Peter Singer’s arguments for infanticide and responded to them with points of agreement and disagreement. So far, I have found that there are many good reasons for thinking the newborn baby is a person with a right to life and no good reasons to think he or she is not. 


  1. Peter Singer, Practical Ethics, 3rd ed. (Cambridge, EN: Cambridge University Press, 2011), 151.
  2. Singer, Practical Ethics, 151.
  3. Singer, Practical Ethics, 151.
  4. Singer, Practical Ethics, 151.
  5. Singer, Practical Ethics, 152.
  6. Paul Chamberlain, Final Wishes: A Cautionary Tale, On Death, Dignity and Physician Assisted Suicide (Eugene, OR: Wipf and Stock, 2000), 112.
  7. Christopher Kaczor, The Ethics of Abortion: Woman’s Rights, Human Life, and the Question of Justice (New York, NY: Taylor Francis Group, 2015), 18.
  8. David Boonin, Beyond Roe: Why Abortion Should be Legal—Even if the Fetus is a Person (Oxford, EN: Oxford University Press, 2019).
  9. Kaczor, The Ethics of Abortion, 18.
  10. Kaczor, The Ethics of Abortion, 18.
  11. Peter Singer, “All Animals Are Equal,” in Jonathan Wolff, Readings in Moral Philosophy (New York, NY: W. W. Norton, 2018), 430.
  12. Singer, “All Animals Are Equal,” in Wolff, Readings in Moral Philosophy, 431.
  13. These are modified versions of Stephanie Gray’s questions in Love Unleashes Life: Abortion and the Art of Communicating Truth (Toronto, ON: Life Cycle Books, 2015), 47-48. Her questions focus more on why fetus’ do not have brains.
  14. Gray, Love Unleashes Life, 48.
  15. Francis J. Beckwith, Defending Life: A Moral and Legal Case Against Abortion Choice (Cambridge, EN: Cambridge University Press, 2007), 132.
  16. I’m modifying my own words from an earlier article. Chris Christiansen, “A Substantive Argument: A Response to David Boonin’s Critique of the Species Essence Argument.” Found at (accessed September 1st, 2022).
  17. Peter Singer verses Stephanie Gray Debate: “Resolved: Abortion is Immoral.” Found at (accessed September 1st 2022).
  18. Scott Klussendorf, The Case for Life: Equipping Christians to Engage the Culture (Wheaton, Il: Crossway, 2009), 54.
  19. Singer, Practical Ethics, 135.
  20. Singer, Practical Ethics, 135.
  21. Christiansen, “A Substantive Argument,” (accessed September 1st, 2022).
  22. Beckwith, Defending Life, 162.
  23. Royal B. C. Museum. Orcas: Our Shared Future. (accessed September 1st, 2022).
  24. Gray, Love Unleashes Life, 52.

Photo by Diana Parkhouse on Unsplash

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Born in Vancouver, B.C., Chris has been married to Amy since 2017. He has a BA in Religious Studies (Youth Leadership), and an MA in Theological Studies (Apologetics). He enjoys acting, evangelism, and debates.

The views and opinions expressed in these articles are those of the author and do not necessarily reflect the official position of Human Defense Initiative.