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Science without Philosophy Can’t Resolve Abortion Debate

Scientific findings do not support opponents of abortion rights without the assistance of unscientific philosophical assumptions, which abortion defenders should challenge.

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There is a new push by prominent opponents of abortion to cloak their position in the mantle of science, and claim that anyone who defends abortion rights is a “science denier.” 1 This push has been the impetus for an onslaught of legislation aimed at restricting abortions on both the state and federal level.

In response to this push, most abortion defenders have reacted by claiming that the anti-abortion partisans are the real “science deniers.”

This whole debate is a mistake. The science invoked by abortion opponents appears to support their case only through the lens of very particular philosophical assumptions. Since abortion defenders do not challenge their opponents’ philosophical assumptions or argue for alternatives, it is little surprise that their battle looks like a rearguard action in a war that has already been lost.

Since abortion defenders do not challenge their opponents’ philosophical assumptions or argue for alternatives, it is little surprise that their battle looks like a rearguard action in a war that has already been lost.
I’d like to consider three prominent specialized scientific claims about fetal development that have motivated the criteria proposed by recent anti-abortion legislation. I claim no authority to assess the merits of the respective scientific claims. But in each case, while the outcome of the specialized scientific debate may have some bearing on questions both doctors and parents sometimes face about the ethics of abortion, it does not bear on the salient question of whether or not women have a right to choose an abortion.

First, many abortion opponents lately cite research suggesting that the fetus may feel pain 20 weeks (or earlier) into pregnancy.2 This claim was the basis for the “Pain-Capable Unborn Child Protection Act,” a congressional bill to ban abortions after 20 weeks that was modeled on a series of state laws.3

Another cohort of abortion opponents cites claims that a fetal heartbeat can be detected as early as four weeks into pregnancy.4 A related series of state bills (and one bill that has not passed committee in the U.S. House) now seeks to outlaw abortion of fetuses with “detectable heartbeats.”5  

Finally, the most strident abortion opponents say that Roe v. Wade was simply wrong to find no constitutional basis for regarding embryos as persons. They say that scientists know that a fertilized ovum with human DNA is a new person.6 Over the years, several states have attempted to pass bills defining personhood as beginning at conception.7

Characteristically, abortion defenders have responded to these proposals by claiming that they are based on bad or no science. Usually this contention is sloppily stated: what their criticisms actually show is that anti-abortion proposals are based on science that is not settled or easy to interpret.

Anti-abortion proposals are based on science that is not settled or easy to interpret.
Consider the fetal pain debate. There is no unanimity among scientists about when the fetus can first feel pain. There are serious questions about whether or not a sensitivity to pain requires the development of the cortex, which fetuses do not develop until the 24th week at the earliest. Even if the fetus can feel pain, there are questions about whether it does, given that it may inhabit the womb in a sleeplike state. A prominent literature review suggests the majority view is that the fetus cannot experience pain until 31 or 32 weeks into pregnancy, well past the point of viability.8 Add to this that philosophically sensitive scientists realize that any pain sensations actually experienced by a preterm and therefore pre-conceptual fetus are nothing like self-conscious pain experienced by an adult.

I have spent some time reading the scientific literature on this topic, and it is clear to me that there is sincere scientific uncertainty about whether there is real fetal pain and, if there is, when it might first occur. Even those scientists most skeptical of the notion acknowledge that rival scientists are often asking legitimate questions.

The outcome of the debate about fetal pain does make a difference to certain questions. Parents seeking to bring a fetus to term have reasons to care about noxious stimuli, whether or not those stimuli are enough to cause genuine pain. Even if these stimuli aren’t enough, there is good evidence that they produce stress responses, which can have long-term health effects for the post-term infant, and these responses can be quelled with the use of fetal analgesia in utero. Birth itself is highly stressful for the fetus, though some scientists think the fetus is adapted to deal with the pain of being born.9

However, these specialized considerations are irrelevant to the philosophical questions of whether or not abortion as such is moral and whether or not a woman should have a political right to choose an abortion. Obviously, the long-term health considerations of potentially painful stimuli are irrelevant to a parent who wants to terminate a pregnancy. And even if a fetus can experience pain during an abortion, this is at most a reason to administer fetal analgesia before the procedure. Even if it is possible to cause unnecessary pain through an abortion procedure, this at most raises questions about the morality of certain abortions, not of all of them. It certainly does not show that there is no right to choose abortion: there are many cases in which people should have the legal right to make immoral choices.

The fundamental philosophical question at the heart of the abortion debate is whether a being like the embryo or fetus has a right to life. Specialized scientific findings will not help us answer this question.
But abortion opponents who invoke “science” in their defense consider none of these scientific distinctions. Writing at National Review, Alexandra DeSanctis claims that it is a “scientifically proven fact” that fetuses can feel pain, citing the presence of pain receptors at six weeks and connections between these and the thalamus at 20 weeks. But simply noting the presence of pain receptors entirely neglects the difference between simple noxious stimuli and real pain. Even pointing to the 20-week connection to the thalamus ignores the serious and entirely unsettled question of whether the thalamus needs to be connected to the cortex for there to be any meaningful experience of pain. And DeSanctis offers all of this as uncontroversially supporting an abortion ban at 20 weeks, as opposed to supporting the simple moral guidance that abortions should be performed only under fetal analgesia.

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In response, abortion defenders do little more than note how much uncertainty and lack of consensus there is among scientists on the question of fetal pain. There’s nothing wrong with this by itself, especially when pundits like DeSanctis present scientific evidence without noting the controversy about its interpretation. But if pointing out this uncertainty is all abortion defenders do, they concede that future scientific research might prove DeSanctis right about fetal pain, and they offer no guidance about how to think about abortion rights in that event. Their unwillingness to distinguish the specialized scientific questions from the philosophical ones—and to engage in actual philosophical debate about those questions—is a big part of the reason I have argued that they are losing the moral debate about abortion.

The fundamental philosophical question at the heart of the abortion debate is whether a being like the embryo or fetus has a right to life. A few ordinary observations should make clear why the specialized scientific findings considered so far will not help us answer this question.

Even if the fetus has a heartbeat or can experience pain, this would not prove that it has a right to life. Animals can experience pain, and even though it may be immoral to torture them, most of us still don’t think animals have the same rights as human beings, if any.10 Animals also have heartbeats, and so do fully brain-dead human beings, but again most people would balk at the idea that they have the same rights as fully mature and conscious adult human beings, if any.11 Someone who thinks otherwise should give a reason for thinking they do have rights, some account of what rights are to justify their position.

Likewise, even though a fertilized embryo has human DNA, this alone does not prove that it has rights. Cancerous tumors and human corpses also have human DNA, and nobody thinks they have rights. Of course a fertilized ovum also has the potential to become a living organism. But an acorn has the genetic potential to become an oak tree, and that doesn’t make it an oak already. So an embryo’s mere genetic potential to develop into a human being doesn’t make it an actual human being already or give it all of the characteristics that provide the basis for the possession of rights.12 To show that this potential is enough to give it rights would require some argument connecting mere potentiality to the possession of rights.

No amount of investigation of embryology or human genetics will show us that some being has rights. Rights aren’t any kind of observable attribute to begin with, and so they are not the sort of thing that can be discovered by the special sciences.

To claim that any being has a right to some status or activity is to claim that this status or activity is a requirement of that being’s existence in society, such that others at least have a reason not to interfere with it. So to conceptualize such a mutually applicable claim as a “right” is to formulate a moral principle guiding our interaction with others. Identifying abstract normative principles like this is the job of philosophy, not the special sciences.13

Having a worldview is like having a pair of glasses you forgot you’re wearing. What happens when you take them off for a moment and try on a different pair?
Showing that the concept of “rights” applies to some being is a non-trivial task. Someone claiming the concept applies would need to show why that being needs what it is said to have a right to and why we have a reason not to deprive it of that. Showing this means identifying the fundamental nature of the being’s needs and articulating the fundamental source of the reasons that guide our actions. This means formulating a theory of human nature and a general moral philosophy—i.e., an integrated philosophical worldview.

Many people don’t see the role of a philosophical worldview in judging the normative relevance of scientific facts because they don’t see the range of different perspectives one can take on the same facts, perspectives that are the products of very different worldviews. The influence of one’s worldview can be hard to notice because it’s the cognitive medium through which one sees and judges everything in life. Having a worldview is like having a pair of glasses you forgot you’re wearing. What happens when you take them off for a moment and try on a different pair?

For example, religious philosophers see the subjects of morality as immortal souls created by a divine being who commands them to respect Him and (sometimes) each other. Depending on their preferred revelations about the intent of the divine, they will make different claims about when a being is ensouled and therefore different claims about when divine commands apply to it. As long as they are unchallenged in their assumption that revelations from a supernatural entity are the standard for identifying what is permitted and what is prohibited, adherents to this worldview can claim that most any scientifically observable characteristic signifies the possession of divinely granted rights.

For a contrasting example, consider secular utilitarians. They see moral agents as transient bundles of sensations whose capacity for pleasure or pain is the only reason dictating how they should respect and relate to each other. For this reason, some utilitarians might conclude that fetuses with that capacity have rights. Still other utilitarians think embryos and fetuses aren’t sentient or self-conscious enough to have this moral status. Whereas religious philosophers depend on their personal view of God’s revelations to decide who has rights, utilitarians depend on their personal emotional reactions (their “intuitions”) about which kind of pleasure or pain matters.

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These examples illustrate how a philosophic worldview involves not only one’s view of human nature and of the good, but also a view of the nature of reality and our knowledge of it. This speaks to the fact that there are reasons for which people avoid considering the role of a worldview, apart from their inattention to its presence. Even those aware of its presence often think there’s nothing that can favor one worldview over another—they think it’s just a matter of opinion. But this evaluation is itself an aspect of a certain philosophical worldview, and not the only one!

In Ayn Rand’s scientific approach to ethics, morality doesn’t codify rumors about how to score a magic ticket to a supernatural world; it gives us principles for living successfully in this world.
In my worldview, philosophy is a science that defines the standards of knowledge that integrate our ordinary observations with the discoveries of the special sciences, for the sake of guiding our decisions about life in the world. While there are many different ways to integrate these discoveries, some are better and some are worse. Some ways of thinking and acting keep us in touch with the real world out there, and some don’t. A truly scientific approach to philosophy seeks to ground one’s knowledge of moral and political norms not in subjective revelations and intuitions, but in observable, objective facts about the needs of human beings who want to live.

In Ayn Rand’s scientific approach to ethics (the approach I agree with), the essential requirement of human life is the use of reason to solve the problem of survival. In this approach, morality doesn’t codify rumors about how to score a magic ticket to a supernatural world; it gives us principles for living successfully in this world. In this approach, morality is not aimed at enhancing or numbing the immediate sensations of pleasure and pain that index success or failure in living; it aims at directly facilitating that success across an entire lifespan.

In Rand’s view, rights enable success in this world by defining a sphere of protection for the freedom from physical coercion individual human beings need if they are to use their reason to learn, create and trade with others in a civilized society. From this perspective, rights are requirements of productive activity, which means they apply paradigmatically to mentally healthy adult human beings, among whom a real harmony of interests is possible.

Given the choice of parents to bring a child into the world and given that child’s needs, the principle of “rights” can be applied to children (and the mentally disabled), but only by extension from the paradigm case and only in qualified ways. Infants, for example, clearly can’t claim or exercise property rights; parents need to be custodians of children’s developing rights while raising them.

Because of their lack of physical individuation from and their direct physiological dependence on an adult human being, the concept of “rights” does not apply to the embryo or fetus.
However, from this perspective, merely being a potential human being isn’t enough for the principle of rights to apply, especially because assigning rights to embryos and forbidding abortions would only serve to violate the rights of an actual adult human being, the mother. Because of their lack of physical individuation from and their direct physiological dependence on an adult human being, the embryo and the fetus are not independent entities that could claim their own sphere of freedom; inherently, they can come into conflict with the interests of the mother. The concept of “rights,” which in part serves to clear social space of conflicts, does not apply to the embryo or fetus.

Furthermore, merely having the capacity to experience pleasure and pain isn’t enough for the principle of rights to apply. Animals have this capacity, but they don’t need and can’t claim or use a sphere of freedom in which to make choices about how to engage in productive activity, because they can’t produce, make claims, or make choices. Pleasure and pain are indicators of their success and failure in their own biological niche, but their success is not necessarily a requirement for human success, and sometimes comes at our expense. Similar things are true for a fetus that results from an unwanted pregnancy.

Invoking our uncertainty about science only obscures the real issue. Defenders of abortion rights need a worldview that provides moral clarity.
Like eyeglasses, one’s philosophical worldview can make one’s vision better or worse. It can help one see farther than one could before, or make things even blurrier. This depends on how much truth one’s worldview contains. Through the lens of religious and some utilitarian philosophies, specialized discoveries in science might seem to help establish that the fetus has rights. But I would argue that this is made possible only by a myopia induced by their revelation- or intuition-based theories of knowledge. A moral philosophy constructed as scientifically as disciplines like embryology and genetics provides us with a theory of rights that brings into full focus the relevant difference between the fetus and a fully individuated human being.

Defenders of abortion rights need to check their philosophical eyewear. Without doing so, they may unwittingly be looking at the world through the same lenses as their opponents. If they don’t challenge the assumptions that rights derive from God’s will or from our capacity for pleasure or pain, they won’t convince anyone that the fetus has no rights and that a woman does. Invoking our uncertainty about science only obscures the real issue. Defenders of abortion rights need a worldview that provides moral clarity.

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  1. A recent piece in The Atlantic spells out how anti-abortion activists increasingly appeal to scientific findings about the fetus to make their case against abortion rights and describes the role these appeals have played in advancing recent anti-abortion legislation. The piece focuses especially on how ultrasound technology has made it easier to look at the embryo and the fetus in utero, while medical science has pushed the time of fetal viability (the cutoff before which Roe vs. Wade mandated abortion rights) to earlier and earlier stages of the pregnancy.
  2. Doctors use two different systems for measuring events in pregnancy: 1) time since conception (C) and 2) time since last menstrual period (LMP). Though LMP is not always the most salient benchmark for anti-abortionists, I will use LMP numbers in the remainder of this article, since most popular discussions of the relevant scientific findings have been expressed in these terms, for reasons I cannot discern. Generally C is two weeks after LMP.
  3. The bill passed the U.S. House of Representatives in October 2017 but failed to advance to the Senate. Such laws would come into conflict with Roe v. Wade’s invalidation of laws prohibiting abortion before viability, which is generally understood as at or around 24 weeks. See Katie Watson, Scarlet A: The Ethics, Law, & Politics of Ordinary Abortion (New York: Oxford University Press, 2018), 159–162.
  4. Converted from C to LMP for consistency. 
  5. Banning abortions this early in pregnancy would do so well in advance of viability and clearly run afoul of Roe v. Wade. Depending on how “heartbeat” is defined, the first heartbeat occurs anywhere between four and twelve weeks LMP. Watson, Scarlet A, 154. Since many women do not even know they are pregnant by this time, “heartbeat” bans would all but prohibit legal abortion. Such a bill was vetoed by the governor of Ohio, but was recently signed by Iowa governor Kim Reynolds and has already been blocked by a judge pending litigation against it.
  6. None other than Pope John Paul II affirmed the same position in his 1995 encyclical Evangelium Vitae, claiming that even if science cannot demonstrate the existence of a spiritual soul at conception, still it proves personhood through the presence of genetic material.
  7. Just this past May, one of these attempts advanced as far as the South Carolina state senate, where it failed to pass.
  8. Converted from C to LMP for consistency.
  9. There is much else to be said about the other debates, as well. For example, there are questions about whether “heartbeat” is the most accurate description of the phenomenon measured at four weeks LMP, given that it is only visible on ultrasound, not audible, and its motion at the earliest stages is not that of a fully matured heart organ. Likewise, regarding claims about personhood and human DNA, while fertilized human embryos surely do have human DNA, advocates of personhood amendments usually simplify the data to suggest that there is a single and obvious “moment of conception.” In fact, it takes 24 to 48 hours for the genetic material from the egg and sperm to merge. (See Ronald Green, The Human Embryo Research Debates: Bioethics in the Vortex of Controversy (New York: Oxford University Press, 2001), ch. 2. Referenced in Steven Pinker, The Blank Slate: The Modern Denial of Human Nature (New York: Penguin Publishing Group, 2003), 224.)
  10. The theory of rights I present later in the essay decisively confirms the suspicion that animals have no rights.
  11. It’s true that religious conservatives mustered a concerted effort against stopping life support for Terri Schiavo between 1990 and 1995. But Terri Schiavo was in a persistent vegetative state (PVS), a condition that falls short of real brain death. Abortion opponents do not, however, generally oppose the medical criteria of brain death. Some do oppose what they take to be loose applications of this criteria, but there is no movement among prominent abortion critics to regard the obviously brain dead who still have a heartbeat as having rights. Even Pope John Paul II acknowledged the acceptability of neurological criteria for the determination of death. In any case, the theory of rights I present later in this essay also weighs heavily against the plausibility of seeing even PVS patients as in possession of rights.
  12. To add one more parallel counterexample, since any cell in your body has human DNA, it too has the potential to become fully human if used by genetic engineers to clone you. I’ve heard the response that the likelihood of any cell being so manipulated is not very high, but it is worth keeping in mind that half of all fertilized blastocysts fail to implant, meaning that even the probability that a fertilized ovum will reach term is below 50 percent. (See Watson, Scarlet A, 151.)
  13. Specialized scientific study by itself can’t answer philosophical questions about rights, or about ethics and moral values in general. This is not because values are independent of facts (I think it’s arguable that they’re not). Rather, it’s because questions about moral values are highly abstract questions that are fundamental to human knowledge and life as such, and as such are the province of the fundamental science: philosophy. More on this follows.
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Ben Bayer

Ben Bayer, PhD in philosophy, is a fellow and director of content at the Ayn Rand Institute and the author of Why the Right to Abortion Is Sacrosanct (2022). Ben is a managing editor of New Ideal and a member of the Ayn Rand University faculty.

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