The Moral Status of the Human Embryo according to Peter Singer: Individuality, Humanity, and Personhood

Peter Singer is a prominent Australian philosopher currently at Princeton University who many might consider to hold radical views on human life. Singer argues that the early human embryo is not a human individual who is a person. He contends that the ‘potential’ of a human embryo existing in the laboratory is not the same as the one who is already implanted in the endometrium of the uterus. Redefining the term ‘potentiality,’ Singer examines the ‘potency’ of the egg and sperm alone as well as jointly. Central to understanding the philosophy of Peter Singer on human life is his rejection of the doctrines of specieism and sanctity of human life. Singer’s thesis is that not all members of Homo sapiens are persons and not all persons are members of the species Homo sapiens. What constitutes a ‘person’ for Singer remains open to be subjectively defined according to the characteristics that are chosen. This remains crucial for Singer in terms of which ‘organisms’ can be subjected to clinical experimentation as regards moral rights. Peter Singer’s arguments against the early human embryo being an individual human person are unconvincing. While admitting that he wants to free us from particular religious views, he fails to make an adequate argument that not all members of Homo sapiens are persons and not all persons are members of Homo sapiens. Peter Singer’s use of logic is consistently followed to the very end of his startling conclusions.

Peter Singer argues that we should reject the view that a human zygote or early human embryo is a distinct human individual.¹ In his view, the ‘identity thesis’ poses serious problems. He takes up the issue of monozygotic twinning where one human embryo splits into two human embryos with the same genetic code. Concerning this procedure he than asks the following questions: Which one of the two human embryos is the original one? Is either of the two human embryos the original one? Is it even possible to know? How are we to understand an early human embryo as a distinct human individual in light of the possible formation of a chimera? If during sexual intercourse, two different human embryos are formed with separate genetic codes and the two of them combine to form only one, how can it be that there was originally one distinct human individual? As Singer asks, who is the baby: Mary or Jane, Mary and Jane, or Nancy?² According to Singer, the issue of totipotency in the early human embryo must also be considered. Since it is well – recognized that the early human embryo consists of totipotent cells, how can one distinct human individual be present? He next considers the status of the 8-cell human embryo. Since it consists of eight totipotent cells, are there not eight distinct individual entities present with each one oriented toward further development? Are there not eight ‘potential’ babies?

Peter Singer than addresses the issue of whether or not a human embryo is a ‘potential’ human being. He states that there are two essential arguments that are relevant when attempting to determine whether the human embryo at fertilization is a human being or merely a ‘ potential’ human being. Singer will argue is that there is no coherent notion of ‘potential’ of which allows the argument potentiality to be applied to embryos in the laboratory.⁴ What is the moral or ‘ontological’ status of human embryos generated in the laboratory by In-Vitro Fertilization (IVF)? In the case of an 8-cell human embryo generated by IVF, Singer observes that this embryo is less likely to implant when transferred to the uterus if growth in culture continues much beyond the eight-cell stage. Singer also observes that while there have been reports of keeping a human embryo alive in culture for nine days, such an embryo has zero probability of becoming a person. Singer’s argument is very clear: while IVF can generate human embryos, they cannot develop into persons unless they are transferred to the uterus; even then, in the best of circumstances, they will most likely not develop into a person.⁵

To understand Peter Singer one must closely examine his views on ‘potentiality’ as related to the beginning of human life. He asks whether there is any difference between the ‘potential’ of the human embryo and the ‘potential’ of the egg and sperm when still separate as well as considered jointly? Singer directly addresses this by referring to the Oxford English Dictionary to define the term ‘potential’ as meaning that it is ‘possible’ for the human embryo to become a human person as possibility is a necessary condition for potentiality. Using that source, Singer argues that it is possible for the embryo to become a person as possibility is a necessary condition for potentiality. Using this logic, Singer recognizes that it is not ‘logically’ impossible for a human blastocyst (an embryo existing five to ten days following fertilization) in a laboratory to develop into a person; he then proceeds to argue that it is not ‘logically’ impossible for a human egg to develop into a person either since parthenogenesis often happens in some species and no logical contradiction is involved in it happening in our species.

Singer raises the question of the ‘potentiality’ of two human blastocysts with one existing in utero and the other existing in vitro. Singer claims that they have entirely different potentials: the one existing in utero is a potential person while the one existing in vitro cannot possibly survive to become a human person. The issue could be stated in another way: if a living human fetus is going to die in utero, is the potential for personhood lost before the fetus dies in utero? For Singer the answer is definitively yes just as it is for the difference between the potential of an eight-cell human embryo in the laboratory versus the potential of a human blastocyst consisting of hundreds of cells. This difference of potential, Singer says, is in the physical sense that is relevant to the present state of both knowledge and technology.⁶ So if it ever becomes possible with technology for human embryos to develop without ever being transferred to a woman, then those blastocysts in laboratories will also be able to become people. Singer now tries to make the same argument with human eggs: if parthenogenesis could occur in humans, every egg would be a ‘potential’ person. Singer is clear that the egg and sperm separately have no special moral status; however, he argues that it seems impossible to use the potential of the embryo as a ground for giving it special moral status. He also states that the egg and sperm have the potential to develop into a mature human being. The environment in which the human embryo develops is most important: it must be allowed to count as an entity and ‘potential’ must be denied to the embryo existing on its own outside such an environment.⁷ Singer claims that parthenogenesis and fertilization are alike – why should the egg after parthenogenesis be regarded as a different individual from the egg before parthenogenesis? His claim is that both biological processes take the development of the egg a stage further; however, the potential of the egg is retained – after all, the egg had the ‘potential’ to become this person all along.⁸ Singer recognizes that ‘potentiality’ is highly significant in terms of the morality of experimentation on an entity; however, his argument is that one cannot prohibit experimentation on or disposal of human embryos and remain unconcerned about how eggs and sperm are treated. In Singer’s view, there is a great difficulty if one tries to explain why the embryo in the laboratory has a potential greatly different from that of either the egg alone or the egg and sperm considered jointly.⁹

To begin to understand Singer on the issue of human personhood as it relates to the beginning of human life, it is necessary to know that he challenges openly the doctrine of the sanctity of human life as the title of his book, Unsanctifying Human Life, so indicates. He admits he wants those involved in medicine to reconsider some foundations of the decisions that are being made. At the very core of this issue is whether or not there is a radical difference between the values of human versus animal lives – both in degree and quality. It is the very idea that human life has such unique value that Singer wants to challenge. He compares and contrasts two situations: that of an infant with Down’s syndrome requiring serious medical care with that of exposing monkeys to addictive narcotics in order to learn the effects of such substances.¹⁰ What is being questioned is critical: is it right to ‘save’ a Mongoloid child when the mother does not want ‘it’ while at the same time slowly and painfully killing monkeys in order to learn something? Now comes Singer’s doctrine against specieism – isn’t it wrong to treat human and non-human animals differently because one said to be superior to the other? Central to this is Singer’s view that in some cases human infants do not have some characteristics that are found in higher non-human animals – the capacity to feel pain, to act intentionally, to solve problems, and to communicate with and relate to other beings. For Singer, to treat a severely handicapped differently than a pig or monkey is discrimination that is rooted in specieism. Drawing upon the analogy of race being nearly always irrelevant to how a person is treated, the species of a being should also be irrelevant. Invoking utilitarianism, Singer makes an argument for drug experimentation on retarded ‘human beings’ rather than utilizing monkeys since fewer subjects would be needed and less suffering would be inflicted. Singer admits that the doctrine of the sanctity of human life is based on discrimination of species. There are human beings – the hopelessly senile and irreparably brain – damaged – who cannot be distinguished from other animals in respect of their potential. This can be understood in the context of Singer’s explicit claim: the right to life is not a right of members of the species of Homo sapiens as Singer demonstrates in his third ‘new’ commandment.¹¹ Not all members of the species Homo sapiens are persons, and not all persons are members of the species Homo sapiens. This can be understood very easily when Singer again turns to the Oxford English Dictionary to define the term ‘human’ as having or showing the qualities or attributes proper to or distinctive of man. For Singer, classifying a ‘being’ as human depends on the subjective qualities or attributes which are distinctive of men and women. If it is subjectively decided that self-awareness or self-consciousness are counted, then severely retarded infants would not be included though they are members of our species. We could simultaneously choose to include apes, dolphins, and other mammals based upon their abilities as human beings. What Singer is pointing to is that our ‘definitions’ of what a ‘human’ is could and perhaps would change which ‘organisms’ or ‘beings’ are subjected to experimentation. Singer admits that this determination is based upon both the meaning and interpretation of the term ‘human’ in a dictionary. In regard to the doctrine of the sanctity of human life, Singer is asking how it is possible to characterize only our human species as sacred. What is it, Singer asks, that makes ‘us’ so sacred that we are distinguished as superior to other animals? Singer begins to address this with his premise that animals and human beings can be seen as equals. We as human beings often claim that all human beings are equal. Singer rejects this emphatically, recognizing that humans have different capacities, needs, sensitivities, abilities to communicate, and different capacities to experience both pleasure and pain.¹² Arguing that those individuals with superior intelligence may not use other humans for their own ends, how is it possible for us to exploit non-human beings? To address this question the experience of suffering in all beings must be considered regardless of the nature of the being. If a being is incapable of suffering or experiencing happiness there is nothing to consider.¹³ The key element for Singer in evaluating all beings is that of sentience. Characteristics such as intelligence are just as arbitrary as are the utilization of race. Specieism allows a human person to place the interests of his own species over that of other species. So how does one decide which ‘organism’ or ‘being’ to use for experimental protocols while not invoking specieism? How does one choose to select among infants who are orphaned or retarded versus adult human beings or animals? For Singer, the answer is clear: for example, a preference for infants and retarded human beings who have no idea of what is going to happen to them as opposed to adults who would know what was going to happen to them. Perhaps orphaned infants and retarded human beings could be used since they are in the same category.¹⁴ Singer’s utilitarianism is clearly brought forth in that ‘beings’ capable of self-awareness, abstract thought, complex communication, etc. are more valuable than those without these capacities; consequently, those without these certain capacities can be used. This forms the basis for ‘preferring’ certain other animals over human beings who have the characteristics of ‘normal’ human beings. Rejecting specieism and admitting that he is invoking utilitarianism, Singer argues that the only experiments that could be justifiably performed on human beings are those that involve an orphaned, irreparably retarded human being.¹⁵ This is based on the fact that the parents do not want the ‘orphan’ coupled with ‘its’ severe lack of ‘capacities’ so that we now regard ‘it’ as ‘non-human.’ This forms the basis for allowing Singer to interpret and define what a ‘human person’ is and is not. Severely retarded infants are not counted as human beings even though they are members of Homo sapiens; on the contrary, apes, dolphins, and perhaps some other mammals could be counted as human beings.¹⁶ This is exactly what Singer means when he argues that not all members of Homo sapiens are persons, and not all persons are members of Homo sapiens.

Where does this leave Singer regarding experimentation upon human embryos? It is recognized that research involving human embryos could be greatly beneficial in overcoming fertility problems and possibly advancing gene therapy and finding cures to many terrible diseases. Singer’s case for human embryonic research is precisely found on the possibility of such great benefits which again reflects his self-acknowledged ethical methodology of utilitarianism. He recognizes that it is not easy to argue that the human embryo is not a human being; nonetheless, he is prepared to do so. While acknowledging that the early human embryo is a member of Homo sapiens, Singer contends that ‘it’ has no more awareness than a lettuce. The reason for this is that the early human embryo has no brain and no nervous system; therefore, ‘it’ does not possess the mental qualities that distinguish ‘it’ from other members of our species. Drawing upon his claim that an acorn is not the same as an old oak tree, Singer claims an early human embryo is not the same as a human adult – ‘it’ is not a human being – again his argument of potentiality. If a couple chooses to use abortion, contraception, or abstinence, they are acting to ensure that a person who might have existed will not exist. Singer claims that those who condemn the destruction of human embryos do not also condemn equally the use of contraceptives and sexual abstinence; hence, they cannot object to destroying a human embryo on the grounds that it is wrong because a person who might have existed will now not exist. This is based on an analogy that there is no distinction between throwing away the ingredients separately or after mixing if it is a cake one is after. Singer wants to utilize the brain to both define the beginning and the end of human life. Arguing that we declare a human person as dead when there is brain death, his claim maintains that we might consider that people are alive when their brains first begin to function. For Singer, brain death is an event and the ‘birth’ of the brain is a gradual process. So, when is it justifiable for Singer to use human embryos for research? The answer given is that only when we reach a stage that the embryo may be capable of feeling pain must experimentation be subject to control since it is at this point that the embryo ranks morally with non-human animals.¹⁷ There is no basis at all for being concerned about a totally non-sentient human embryo as it can have no ends of its own.

The doctrine of the sanctity of human life, Singer says, comes out of the Christian ethical and cultural tradition in terms of a distinction between members of our species and those of other species. While acknowledging that other cultures have not always promoted the doctrine of the sanctity of human life, Singer argues that Christianity had an impact in changing attitudes in regard to abortion and infanticide in Europe. This was grounded in a new religion with theological motivation that emphasized that all who are born of human parents have an immortal soul and a destiny of either eternal happiness or damnation. The belief of an immortal soul that is either rewarded or punished in Christianity is the basis for the separation of Homo sapiens from other species as far as the significance of their lives is concerned.

What does Singer offer as a solution? One possibility is to recognize the dignity of other species yet to consider it legitimate to kill retarded human infants in painful ways for experimental purposes even when useful knowledge may not come from the experiments; in addition, we could give up any moral objectives against rearing and killing these infants for food. Finally, while treating our own species with respect, we can change our attitudes to members of other species such that we consider it wrong to kill them because we like to consume them or even because they are in intractable pain. Finally, we change our attitudes towards both humans and non-humans so that they come together at some point in between the present extremes. Singer’s ultimate goal is for us to free ourselves from a worldview depending on some specifically religious premises which then will allow it to be shown that the early human embryo has no intrinsic value and no right to life.¹⁸ Singer’s claim is that there is no evidence that taking the lives of members of our own species under certain special circumstances will have any kind of contagious effect on our attitudes to killing in other circumstances.¹⁹

I will begin a formal critique by examining Singer’s claim that an early zygote or embryo is not a distinct human individual as demonstrated by monozygotic twinning. When the bacterium Escherichia coli divides by binary fission, one E.coli cell splits into two daughter cells neither of which is the original. None of us doubts, however, that there was one unique individual E.coli cell. The same process occurs every day in somatic cells in our bodies. For example, when a lymphocyte (a white blood cell) undergoes mitosis, two identical daughter cells result from cellular division and neither of them is the original one. None of us would doubt that there was an original unique individual human lymphocyte – – it simply gave rise to two identical lymphocytes by cellular division. There are numerous examples of both prokaryotic and eukaryotic cells in nature that upon dividing give rise to two identical daughter cells neither of which is the original one. But what about in the case of two human embryos combining together to form one – a chimera? A chimera is composed of two distinct genetic tissues. While chimeras have been observed in embryonic mice and form by a process of recombination, if they occur in human embryos, it is very rare.²⁰ It is very likely not possible to know if one or both of the individual embryo(s) continues to exist or if there is a new (third) individual human embryo.²¹ If chimeras do form in human embryos, it is a reverse process of what I described in cellular division: two individual unique human embryos ‘combine’ resulting in a third unique individual human embryo that may or may not ‘contain’ one of the original two. It is important to recognize that monozygotic twinning is very rare – it occurs only .22% of the time.²² Also, it is not known with absolute certainty that chimeras form in human embryos; if they do, it is very rare. Singer is arguing against accepting that an early human embryo is a distinct human individual using ‘precepts’ that are based upon ‘the exceptions to a rule’ – monozygotic twinning and chimeras. The attempt to establish or refute the human individuality of human embryos should be based upon the normal, expected observations or ‘rules’ of human embryology and not their exceptions. But what about the issue of totipotency in the early human embryo? It is well – established that the early embryo does consist of blastomeres that are totipotent. But this does not mean that each ‘blastomere’ is a single individual by itself. It is correct that a totipotent cell, by definition, is able – in theory – to form a complete individual organism.²³ While a four-cell embryo consists of four totipotent blastomeres, each blastomere constitutes a part of the entire whole as long as the totipotent blastomere remains together.²⁴ What happens if one blastomere is ‘teased off’ the human embryo? Is ‘it’ a human zygote? The best answer that can currently be provided is that up to the four-cell embryo, the removal of a totipotent blastomere could possibly by equivalent to a human zygote.²⁵ Even if this turns out to be true, it does not preclude that originally there was one distinct individual human embryo. It is known that in many plants there are totipotent cells. If one of these such cells is ‘removed’ and placed in culture, ‘it’ can give rise to another plant. Do we doubt there was one individual plant that gave rise to the second one. Or take the case of pluripotent stem cells (those which are somewhat committed) that are found in the bone marrow. If we isolate such a stem cell from an adult – pluripotent or totipotent – and induce it to becoming a particular ’tissue’ or a human zygote, does that mean there was not a distinct individual human being originally? Singer’s arguments of monozygotic twinning, chimeras, and totipotency fail to constitute definitive proof that the early human embryo is not a human individual. .

Are human embryos potentially persons? Singer argues that an eight-cell embryo generated by IVF in the laboratory is a potential person if ‘it’ is transferred to the uterus for implantation where it has a ‘chance of possibly becoming’ a person.²⁶ A human embryo generated by IVF at nine days, however, has zero probability as a blastocyst of becoming a person. St. Thomas Aquinas defines potency as that which is necessarily related to act; in other words, there is never a case of potency without act.²⁷ The human embryo, therefore, is in act in regard to what it is now; ‘it’ is in potency in regard to what ‘it’ may subsequently become. Potency, therefore, recognizes that the human embryo who is alive in the laboratory – whether at the four-cell stage or the blastocyst stage (consisting of hundreds of cells) – is already in act and hence is a human being who is alive. ‘It’ already is a human being in regard to the fact that ‘it’ is alive and is an admixture of both potency and act. It is true that very many human embryos generated by IVF will not result in a live term-birth. Yet as long as the human embryo remains alive in vitro or in utero, we have present a living human being at the earliest stages of biological development. Singer’s utilitarianism is manifested by his argument: only those human embryos that have a possible chance of ‘becoming’ persons with certain qualities are ‘potential’ persons. Singer has rejected the classical notion of potency from philosophy and substituted for it the definition from the Oxford English Dictionary. Whether or not a human embryo in the laboratory can ‘potentially’ become a human being, for Singer, depends upon our current stage of biomedical technology – it has nothing to do with the ontology of the being who is an admixture of both potency and act.

What about parthenogenesis? Singer argues that it is not logically impossible for a human egg to develop into a person. I would first note that there is absolutely no evidence of parthenogenesis naturally occurring in our own species. It could, however, possibly occur if one were to ‘bypass nature’ and manipulate the egg as was done recently by scientists at Advanced Cell Technology. Parthenogenesis in human beings results in the replication of only the maternal DNA; hence, all of the chromosomes are derived from only the egg. It is very likely that such a so-called ‘human embryo’ as is generated by parthenogenesis is similar to the hyaditiform mole. Both of these conditions are generally thought to be incompatible with true human (embryonic) life from the very beginning. I would thus challenge Singer’s claim that parthenogenesis is not a logical contradiction in our species and that the human embryo resulting from it is alive. Singer again uses the same utilitarian analogy with a human fetus that he used with a human embryo: if the human fetus in utero is going to die, then there is no potential for personhood. This argument fails to recognize that the nature of a being who is an admixture of potency and act is not determined by the current state of technology. The nature of any being exists both objectively and independently apart from such technology. It has no bearing on whether or not the ontological status of ‘what’ is present is a human being. All the current technology informs us is perhaps how long the new human being that was generated might survive. While Singer argues that parthenogenesis and fertilization are alike, there is a radical difference between a zygote possessing both maternal and paternal chromosomes versus one whose chromosomes are entirely maternal. While Singer is correct that both biological processes take the development of the egg a stage further, human fertilization does so in a manner usually compatible with human life while human parthenogenesis does not. But what about Singer’s claim that if technology developed such that an egg could ‘induced’ to become a human zygote then every egg could be seen as a potential person? Every egg, by its very nature, is incapable of becoming a human embryo or ‘potential’ person on its own just as every sperm is also incapable by its nature of becoming a human embryo on its own. It is therefore not possible to say that an egg or sperm by itself and its nature is a ‘potential person’. If it becomes possible to manipulate stem cells and induce them to become a living human embryo, such stem cells are not by their nature ‘potential persons’. Take the case of Dolly who was cloned. Was the somatic mammary gland cell used, by its very nature oriented to becoming a ‘potential sheep’? Clearly, it was not; however, two-hundred and seventy-seven attempts to generate a ‘Dolly’ finally resulted in a living embryo that was brought to term – Dolly. If it becomes possible to manipulate and induce a hematopoietic stem cell from the bone marrow to become hepatic cells or tissue of the liver, that stem cell by its very nature in the bone marrow was not a ‘potential’ hepatocyte. So, why is it that for Singer the human embryo in the laboratory has no potential that is greatly different form that of the egg alone or the egg and sperm considered jointly?

To address this critical issue, it is necessary to discuss human personhood as it relates to the beginning of human life. Singer openly admits that he wants to challenge the doctrine of the sanctity of human life. It is now necessary to examine the very nature of a human being as related to a human person from the beginning of ‘its’ existence. For Singer, we can only count as ‘persons,’ those beings who clearly manifest certain qualities such as sentience or the capacity to feel pleasure or pain. Since a living human embryo at four weeks cannot possibly experience pain or pleasure since there is no brain or nervous system that is organically manifested, such an embryo cannot be a human person. In Singer’s view, the early human embryo is comparable to a lettuce.²⁸ He aims to challenge everyone – particularly the medical profession – to examine the very idea of why should human life have such unique value. To do this we must examine the very nature of a human zygote – a human embryo. When IVF is employed to generate a human zygote in the laboratory, certain properties can immediately be observed: the synthesis of human proteins, the replication of DNA, and the division (mitosis) of the human embryo as growth continues. These observations or ‘effects’ that are vegetative lead us to their cause: a human rational soul. The five genera of powers in the soul of a human person are vegetative, sensitive, appetitive, locomotive, and intellectual.²⁹ The only ‘effect’ which we can observe at fertilization in the human zygote is vegetative – this is the case for the human zygote generated by IVF in the laboratory as well as in utero by conjugal intercourse. But how could it be possible to describe a human zygote as a human person when only vegetative operations of the soul are manifest? I argue that it is not possible to accept a dualistic philosophy as regards all of the powers of the human soul; in other words, the observance of vegetative functions in the human zygote necessitates that all of the powers of the human rational and intellectual soul must be present as the Council of Vienna taught in 1312.³⁰ The church teaches that it is the soul which animates the body and that the soul is the form of the body.³¹ That we observe immediately upon fertilization vegetative operations of the soul necessitates that all of the powers of the human soul – vegetative, sensitive, appetitive, locomotive, and intellectual – are by necessity present in potency. While the sensitive, appetitive, locomotive, and intellectual powers cannot be expressed or their effects observed in the human zygote due to the necessary organic structures that are not yet developed, there is an alive ‘being’ who is both in potency and act: a living human person at the earliest possible stage of biological development referred to as a human zygote who is a human embryo. It is St. Thomas Aquinas who allows us to properly state that the human zygote does not contain the soul; rather, it is the soul that contains the human zygote. The human zygote is a human being with a rational nature because of a human rational soul. It is this definition of person that Thomas Aquinas embraces: a person is an individual substance of a rational nature.³² The human zygote – who is in possession of a rational soul and hence has a rational nature – is a human person.

The idea that human persons are somehow superior to non-humans is for Singer specieism. He asks how it could be possible to argue that a severely retarded infant or an anencepahlic one is superior to a ‘normal’ baboon. To understand this properly requires a theological foundation: when God created human persons, He did so making them in His own image and likeness (Genesis 2:19-20; 9:1-4). The basis for the intrinsic value and inviolable dignity of each human person from the moment of conception reflects the fact that each human being is by their soul made in the image and likeness of God. This is why the church has stated that the human being must be respected – as a person – from the very first instant of his existence.³³ John Paul II has noted that only man is capable of ’tilling the earth’ and ‘subduing it’.³⁴ It is in this context that human beings have a unique identity and hence dignity that the non-human animals do not share. Though an anencephalic infant lacks an upper brain, he or she manifests vegetative and locomotive operations of the soul; the intellectual, sensitive, and appetitive powers are present in potency but cannot be expressed in act because the necessary organic matter is absent: the upper brain. What about a severely handicapped infant? Many of these infants are capable of experiencing pleasure and pain; however, what is most important to recognize is that they too have a rational soul that makes them a human person. That they may have extremely poor capacities for abstract thought and complex communication reflects a pathology on the organic level of matter – it has nothing to do with the metaphysical powers of their soul but rather in the exercise of those powers. Even though the severely handicapped infant may not function as well as some animals, such a human infant still possesses intrinsic dignity because of the existence of a human soul that is the substantial form of the living composite of body and soul. Though an orphaned infant who is ‘retarded’ or ‘anencephalic’ may not be able to exercise particular metaphysical powers of being due to abnormalities involving organic matter (structure and function) in the same manner that Koko the baboon can, such an infant is a human person who is a member of the species of Homo sapiens because of the existence of a human rational soul. On the other hand, Koko shows no evidence of being able to engage in human reflective judgment or analysis any more than dolphins can do so. Singer’s argument that a severely retarded infant who is orphaned need not be classified as a human ‘person’ while certain nonhuman animals could be classified as a ‘person’ remains thoroughly unconvincing.

But what about the dignity of animals? Singer has a valid point when arguing that animals should also be respected – the question becomes the dignity of non-human animals compared to that of human beings who are made in the direct image and likeness of God as reflected by the human rational soul. It was only to human beings who have a rational nature that God gave the universe to in terms of dominion that is not absolute. Creation must be respected precisely because it is God’s creation; hence human beings can be said to be ‘stewards’ of the earth. Human beings, therefore, have an intrinsic dignity that surpasses the dignity of animals in that it is only human beings who have a rational soul that reflects humans beings being made in the direct image and likeness of God Himself. The care of animals is entrusted to human beings by God which means that animals should be respected even though they do not possess a rational nature and hence do not have a rational soul. To compare a severely handicapped human being to one of the higher non-human animals and argue that the non-human animal is more ‘valuable’ than the ‘defective’ human being is utilitarian. It fails to recognize that the severely handicapped human being still possesses a rational nature due to a rational soul which none of the animals have. The philosopher, Gary Varner, recognizes that it is possible to attribute certain moral rights to animals while simultaneously using them for some types of medical research that is justified.³⁵Varner’s view is a prudent one and even though he does not specify the exact type(s) of research, his position is consistent with that of the Catholic Church: medical and scientific experimentation on animals is morally acceptable practice if it remains within reasonable limits and contributes to caring for or saving human lives.³⁶ Singer’s effort is to re-define what the term ‘human’ means and than to argue that it is possible for ‘human’ to include an ape or a dolphin while excluding a human being who is alive yet severely incapacitated. But what is the relationship between human infants and dolphins in their use of reason? St. Thomas Aquinas recognizes that nonhuman animals have a certain type of ‘judgment’ from which they act.³⁷ Human infants, like dolphins, have prelinguistic reasons for actions, and the complexity of the relationships between the goods that they pursue and the means that they adopt in order to achieve them matches that exhibited by dolphin reasoning. Human infants, however, go beyond the reasoning characteristic of dolphins when they become able to reflect on and pass judgment on the reasons by which they have been guided – dolphins have shown no such evidence. Nonhuman animals do not have the same power of ‘judgment’ as human beings do.³⁸ This utilitarianism of Singer’s methodology against ‘specieism’ reflects the reality of what Alasdair MacIntyre observes in After Virtue: the rejection of the classical Aristotelian view of the world which allows for the moral vocabulary to re-defined.³⁹

Is it justifiable to use human embryos for research that could possible benefit humanity? For Singer the fundamental question as to whether or not this is justifiable begins with sentience. Since human embryos do not have sentience for at least twenty-eight days after fertilization, Singer sees no problem in using ‘them.’ Only when a brain and nervous system appear do we need to be concerned about the human embryo possibly suffering. Prior to this point in time, research on human embryos is not an issue for Singer. What about using an infant for such research? Singer replies that it would be justifiable to use orphaned infants who are severely handicapped. Singer’s argument is that just as brain death defines the end of life , so should ‘brain birth’ define the beginning of life. I would note that while brain death has been largely accepted to define the death of a human person, its acceptance is not universally absolute and research continues to occur on this most significant issue.⁴⁰ Singer’s view on judging whether to use human embryos for research based upon sentience and the benefits to be obtained is no different from his view on using an orphaned handicapped infant that nobody wants: using his self-admitted utilitarianism, he consistently and logically follows his moral principles to their disturbing conclusions.⁴¹

Singer is very clear that he intends to challenge the doctrine of the sanctity of human life which he says comes out of a Christian tradition. Emphasizing that Christianity taught the existence of an immortal soul, he argues that this teaching was the basis for specieism – believing that human beings are ‘superior’ to other animals. This doctrine also affected the practices of abortion and infanticide. Singer’s writings seem to take a somewhat bellicose position toward the very notion of God and Christianity as well as religion as demonstrated by his call to free ourselves from views that depend upon religion. He seems to reject the idea not only of a god but of God also creating human beings in His own image and likeness and giving humans dominion over the universe. I would argue that the rejection of God creating humanity in His own image and likeness undermines the very notion of an objective and inviolable dignity of human beings. Any perceived value or use of such beings must necessarily be defined in a highly subjective and arbitrary manner by an individual(s) deciding what moral status to assign to all living beings and hence what moral rights all such beings are accorded. While Singer does not explicitly state that he rejects God and His creating humanity in His image and likeness, one wonders how Singer could do anything but reject God as I have so described Him. If this is what Singer is doing, it helps one better understand his consistent ethic of utilitarianism regarding human life and how the ‘usefulness’ or ‘value’ of any particular ‘being’ is always judged according to the principle of utility.

In this paper, I have examined the arguments of Peter Singer in terms of the moral status of the human embryo. While Singer has argued against the early human embryo being a human individual person, his arguments remain unconvincing from both a scientific and Aristotelian/Thomistic perspective. Rejecting specieism and the doctrine of the sanctity of human life, Singer has re-defined critical elements of the moral vocabulary such as ‘potential’ and ‘person’ against the classical notion. This effort has allowed him to advance his position that not all members of the species Homo sapiens are persons, and not all persons are members of the species Homo sapiens. This serves as the basis for Singer’s consistent utilitarian ethic that allows for the value of each life to be subjectively judged in terms of ‘its’ capacities and being desired by others versus the benefit(s) that such a life could provide to others from being used, for example, for research. Rejecting the idea that every human life has an objective, inviolable dignity rooted in the doctrine of the sanctity of human life, the principle of utility for Singer serves to determine who should live and who should die. Do we really believe Peter Singer’s claim that taking the lives of members of our own species under certain circumstances will not encourage us to kill in other circumstances? The evidence available to us from physician – assisted deaths in the Netherlands suggests the very opposite.⁴² The widespread acceptance of abortion in our own culture indicates the consequence of the devaluation of human life in utero against what Peter Singer is arguing.

End notes:

1. Peter Singer, Unsanctifying Human Life, ed. Helga Kuhse (Malden: Blackwell Publishers Ltd., 2002) 188.
2. Singer 190.
3. Singer 191.
4. Singer 200.
5. Singer 201.
6. Singer 201.
7. Singer 205.
8. Singer 206.
9. Singer 212.
10. Singer 218.
11. Singer 186.
12. Peter Singer, “Animal and Human Beings as Equals,” Animal Regulation Studies 2(1979/80): 165.
13. Singer Animal 167.
14. Singer Animal 168.
15. Singer Animal 171.
16. Singer Unsanctifying 222.
17. Peter Singer and Helga Kuhse: “The Ethics of Embryo Research,” Law, Medicine, and Healthcare, 14 (1986), 137.
18. Singer and Kuhse, Issues, 133.
19. Singer, Unsanctifying 231.
20. Ronan O’Rahilly and Fabiola Muller, Human Embryology & Teratology, 3rd ed. (New York; Wiley-Liss, 2001) 10.
21. Paul Flaman, “When did I Begin? Another Critical Response to Norman Ford,” The Linacre Quarterly 58(1991): 45.
22. Ward Kischer, “A Commentary on the Beginning of Life: A View from Human Embryology,” The Linacre Quarterly 60(1996): 75.
23. William Larsen, Human Embryology, (New York: Churchill Livingstone, 1993) 28.
24. Flaman 41.
25. Ward Kischer. Telephone Interview. 1 Nov. 2002.
26. Singer, Unsanctifying 202.
27. St. Thomas Aquinas, Summa Contra Gentiles I, 16: trans. Anton Pegis (London: U of Notre Dame, 1955) 100.
28. Singer, Issues, 134.
29. St. Thomas Aquinas, The Summa Theologica, (New York: Benziger Bros., 1948) Ia, q. 78, al.
30. J. Neuner and J. Dupuis, The Christian Faith (New York: Alba House, 1982) 120.
31. Catechism of the Catholic Church 2nd ed. (Rome: Libreria Editrice Vaticana, 1997) 93.
32. St. Thomas Aquinas, Summa Theologica, 1a, q.29, a1.
33. Congregation for the Doctrine of the Faith, Donum Vitae (Boston: Pauline Books & Media) 12.
34. John Paul II, Original Unity of Man and Woman, (Boston: St. Paul Editions, 1981) 56.
35. Gary Varner, “The Prospects for Consensus and Convergence in the Animal Rights Debate,” Hastings Center Report 24, no. 1(1994):27.
36. Catechism 581
37. St. Thomas Aquinas, The Summa Theologica, Ia, 84, 1.
38. Alasdair McIntyre, Dependent Rational Animals: Why Human Beings Need the Virtues, (Chicago: Carus Publishing Co., 1999) 55.
39. Alasdair MacIntyre, After Virtue, (Notre Dame: University of Notre Dame Press, 1984) 81.
40. M. Lutz, “Statement Against the Report on Cerebral Death by Professor Corrado Manni” The Dignity of the Dying Person: Proceedings of the Fifth Assembly for the Academy for Life. Ed., Juan Dios Vial Correa and Elio Sgreccia. (Libreria Editrice Vaticana, 2000) 119-122.
41. Mark Oppenheimer, “The Utility of Peter Singer: Who lives? Who dies?” Christian Century , July 3-10, 2002: 25.
42. Richard Fenigsen, “Physician – Assisted Death in the Netherlands: Impact on Long-Term Care,” Issues in Law & Medicine, 11.3 (1995): 284.