The purpose of this paper

David Benatar argued in his 2006 book that being born is always worse than not being born, which he demonstrated using the idea of the asymmetry of pleasure and pain. His argument sparked a controversy among philosophers. Today, there are groups of antinatalists who try to persuade people not to give birth to children. This topic is closely related to reproductive ethics, population ethics, and environmental ethics.

In academic philosophy, much effort has been devoted to debating whether the logic of antinatalism is correct.Footnote ¹ What this paper does is different. It considers one type of antinatalism—the antinatalism that argues that “sentience” is the most important factor when considering the reproduction of biological creatures—and examines what kinds of problems antinatalists must face when pursuing their mission. Hence, the relationship between sentience and antinatalism is the main topic of discussion here.

There is no consensus on the definition of antinatalism.Footnote ² Masahiro Morioka has classified antinatalism into the following four types: (1) pain avoidance theory, which argues that because living a life necessarily involves pain, being born is always worse than not being bornFootnote ³; (2) David Benatar’s type, which argues that while the existence of pain makes being born worse than not being born, the existence of pleasure does not make being born better than not being born, and therefore being born is always worse than not being born; (3) Russian roulette theory, which argues that if the human species continues to procreate, the life of at least one child will become desperately bad, and therefore, we must give up all births; and (4) nonexistence of consent, which argues that because all procreation is done without the consent of children, it must not be done.Footnote ⁴

This paper concentrates on the first three, because they share the very important idea that procreation is very bad in that it brings future children into a world of pain and suffering. What we must do is stop giving birth to children and prevent all human pain and suffering from emerging in this world. I call this principle “pain-emergence preventism”Footnote ⁵ (in the following, the word “pain” is used to mean “pain and suffering,” for brevity). According to this principle, the emergence of pain is inevitably bad and cannot be offset by pleasure, even if the pain is very small. Benatar crystallizes it this way: “One of the implications of my argument is that a life filled with good and containing only the most minute quantity of bad—a life of utter bliss adulterated only by the pain of a single pin-prick—is worse than no life at all.”Footnote ⁶

If we take the principle of “pain-emergence preventism” seriously, it is clear that we must consider not only human pain but also the pain of all sentient creatures because it is discriminatory not to treat humans and sentient creatures equally with regard to the same issue. This type of discrimination is called “speciesism,” and it has been widely criticized in the field of animal ethics.Footnote ⁷ It is not strange to argue that sentience-based antinatalism should follow this kind of nonspeciesism. This is because both humans and sentient animals can feel pain, and thus, the emergence of pain must be prevented for both humans and sentient creatures equally. If antinatalists think that the prevention of the emergence of pain by stopping procreation is the most important issue for them, they must adopt antispeciesism for their antinatalism.

This paper considers the type of antinatalism that argues, based on the principles of pain-emergence preventism and antispeciesism, that no sentient beings—including humans—should be born. Of course, there are competing theories of antinatalism, such as anthropocentric antinatalism, but the word “antinatalism” in this paper is used to refer primarily to the above type, which is sometimes called “sentiocentric antinatalism.”Footnote ⁸ The sentience-based antinatalism is our target.Footnote ⁹

Regarding sentiocentric antinatalism, Joona Räsänen’s 2023 paper entitled “Should Vegans Have Children? Examining the Links Between Animal Ethics and Antinatalism” and a subsequent criticism by Louis Austin-Eames are very important for this paper because they discuss the issue from the perspectives of both antinatalism and sentience. Räsänen writes that “ethical veganism and antinatalism share the core assumption that pain and suffering is bad and should be avoided. From this, I have argued that ethical veganism and antinatalism go hand-in-hand and that therefore, ethical vegans should not have children.”Footnote ¹⁰ Austin-Eames, criticizing Räsänen’s argument, writes that “vegans who accept the utilitarian argument for veganism need not accept the utilitarian argument for anti-natalism” because “there is asymmetry between the arguments made for veganism and those made for anti-natalism”; therefore, it is “permissible for vegans to have children.”Footnote ¹¹

I appreciate their discussion, which tries to link antinatalism with animal ethics by way of sentience, but the problem is that they confine their discussion to the pain and suffering of domesticated animals and do not extend their scope to those of wild animals, which also experience enormous pain and suffering in the wild. Of course, because their main issue is veganism, the most immediate ethical problem for them should be factory farming. However, theoretically speaking, the philosophical discussion of antinatalism and animal ethics should be extended to include the pain and suffering of all sentient creatures on earth.

The purpose of this paper is to explore the essence of the logic that lurks behind sentiocentric antinatalism. This paper discusses the extermination of all creatures on earth and the indefinite monitoring of creature emergence, but this is done only for the purpose of clarifying the hidden logic of sentiocentric antinatalism. I believe that this kind of conceptual analysis has its own significance in the academic discussion of antinatalism. Readers will find three important results of my conceptual analysis in the conclusion of this paper.

The following sections illustrate that sentiocentric antinatalists would inevitably face a paradox in the pursuit of their goal and that they would have to bear certain obligations to survive for the purpose of preventing the procreation of sentient creatures. To explore these obligations, I trace four phases that sentiocentric antinatalists would face and consider what kinds of obligations would arise in each of these phases.Footnote ¹²

Phase one: Until the extinction of the human species

Antinatalism must be based on persuasion, not coercion. Antinatalists want all people to voluntarily refrain from having children through birth control methods or voluntary sterilization surgery. This is the standard view of today’s antinatalists. Häyry and Sukenick, after proposing their antinatalist codes of conduct, write that “we would be pleased if everyone acted like us in this respect.”Footnote ¹³

Here, a difficult problem arises. Realistically speaking, no matter how earnestly antinatalists try to persuade, it would be almost impossible to convince everyone in a short period of time not to give birth to their children. Of course, the ideal path for antinatalists would be for all the human beings to suddenly stop procreating, the number of births to become zero, and humanity to disappear gradually from older to younger generations, while carefully managing the shrinking size of society over the course of a century or so. However, scenarios in which this idealistic outcome does not occur must also be taken seriously, given that pronatalist human behavior patterns do not easily vanish overnight. Antinatalists should not turn a blind eye to this reality.

This shows that, in order to carry out their project, antinatalists would likely need future generations to pass it on, which means that their project depends heavily on the birth of future children. Of course, it is not antinatalists who create children; those who create them are pronatalists. Nevertheless, it appears highly probable that antinatalists need the birth of new generations to pass on their project. I call this the first stage of the “paradox of antinatalism,” in which, in order to put an end to procreation, antinatalists would likely end up relying on the children to whom pronatalists will give birth (this is still an incomplete form of the paradox; see the following sections).

Antinatalists can take at least three attitudes toward this paradox.

The first is the following attitude:

This is the argument that since there is no dependence on their own procreation, there is no paradox of antinatalism. Because they are simply trying to utilize the children that pronatalists are expected to create, pronatalists are to blame for the evil of procreation, not antinatalists.

The second is the following attitude:

This is the argument that if it is necessary to achieve the goal of antinatalism in the long run, antinatalists should be allowed to ignore the evil of procreation by pronatalists and utilize it as a mere instrument for their ultimate purpose.

The third is the following attitude:

This is the argument that since the paradox of antinatalism is unavoidable, the only choice antinatalists can make is not to pass on their mission directly to future generations, but simply to wait for a time when children will voluntarily and intentionally realize the truth of antinatalism and begin to choose not to give birth.

We can say that in the above three cases, antinatalists have an obligation to pass on their mission to future generations if they attempt to live faithfully by their antinatalist principle, even if they end up utilizing pronatalist procreation as an instrument or tool to achieve their goal. This means that antinatalists must survive as a group until the time of human extinction. I call this obligation antinatalists’ “first obligation to survive.” The goal of our antinatalists in Phase One is to reduce the human population and converge it into a small group of antinatalists.Footnote ¹⁴

Here, I would like to emphasize once again that the purpose of this discussion is not to make a sound simulation of a future antinatalist society but to explore the central core of sentiocentric antinatalism by analyzing the conceptual structure of reproduction it wishes to create in the future society.

Phase two: Until the extinction of nonhuman sentient creatures

This paper considers the antinatalism that argues that no sentient beings should be born (sentiocentric antinatalism). I do not delve into the biological aspects of sentient creatures in detail here, but it is nearly certain that creatures that have a central nervous system and also pain receptors within that system can feel pain.Footnote ¹⁵ In the rest of this paper, the term “sentient creatures” is used to refer to such biological beings.Footnote ¹⁶

If sentiocentric antinatalists are sincere in their principle, then it is clear that they wish to put an end to the procreation of all sentient creatures on earth. Since nonhuman sentient creatures cannot intentionally or voluntarily stop themselves from procreating, this should be the task of human beings. The best way to accomplish this is to stop it artificially, for example, by using certain drugs or genetic technologies developed for the extinction of such creatures—before the extinction of the human species. Hence, the best solution would be to simultaneously promote both the extinction of the entire human species through pregnancy avoidance and the extinction of all sentient creatures through biotechnologies and then, after confirming the extinction of all nonhuman sentient creatures, to put an end to the reproduction of the remaining human beings. Since it would take time to confirm the extinction of all nonhuman sentient creatures on earth, antinatalists would have to continue living for some time until the confirmation is complete.

The sterilization of all nonhuman sentient creatures sounds very strange, but please remember that we sterilize pets, such as dogs and cats, and animals such as deer, goats, and some birds to prevent population growth.Footnote ¹⁷ Currently, the sterilization of nonnative fish is being developed for the purpose of extinction. These are the methods that our society has discovered and applied to animals. Sentiocentric antinatalists simply want to extend the scope of its application to all sentient creatures.

Readers may wonder if there are any people who actually think about such a strange project. I have never read academic papers discussing this topic in detail, but Benatar writes in his 2006 book that “[m]y argument applies not only to humans but also to all other sentient beings,”Footnote ¹⁸ suggesting that his antinatalist argument can be applied to nonhuman sentient creatures as well; however, he does not further discuss it there. He simply writes, “Although I think that coming into existence harms all sentient beings and I shall sometimes speak about such beings, my focus will be on humans.”Footnote ¹⁹ On the Internet, one can find serious discussions about this issue. For example, Magnus Vinding, in his 2016 essay, advocates “wildlife antinatalism,” which means “to prevent the births of nonhuman beings in nature.” His conclusion is this: “[I]t would be better if (at least) most non-human beings in nature were prevented from coming into existence, and to encourage both discussion of this controversial claim and research into the degree to which such prevention is practically realizable.”Footnote ²⁰

Sentiocentric antinatalism would argue that the extinction of all wild animals is much better than a situation in which animals kill and eat each other, causing great pain and suffering on earth. Some may think that simply sterilizing carnivores will suffice to end the killing and eating of sentient creatures on earth, but this would be wrong. The supporters of sentiocentric antinatalism would say that because even herbivores feel pain from sickness, aging, and accidents, they should also be sterilized.Footnote ²¹

As pointed out earlier, in order to accomplish sterilization, sentiocentric antinatalists must continue to live until the extinction of all nonhuman sentient creatures is actually confirmed. This is the “second obligation to survive” that sentiocentric antinatalists must bear. Here arises a slightly modified paradox: in order to put an end to the emergence of sentient creatures, sentiocentric antinatalists have to survive until the extinction of all nonhuman sentient creatures. This is the second stage of the paradox of antinatalism.

Some might criticize this idea by saying,

However, this argument is problematic from the viewpoint of sentiocentric antinatalism because the prevention of pain through avoidance of childbirth must apply equally to humans and nonhuman sentient creatures. Sentiocentric antinatalists would say that considering only human pain and ignoring the pain of nonhuman sentient creatures is blatant speciesism and should never be allowed.Footnote ²²

Imagine the following case. Antinatalists have succeeded in reducing the human population, and only a small number of antinatalists remain on earth, but a large number of nonhuman sentient creatures are still alive and unsterilized. If this trend continues, humans will become extinct before the sterilization of all nonhuman sentient creatures is completed. What should antinatalists do? I believe that in such a case, sentiocentric antinatalists should give birth to their own children and pass on their mission of sterilizing all sentient creatures to future generations. Of course, by doing this, the children to be born will have to suffer unnecessary pain that would not exist without their births, and there is no guarantee that the children will also become antinatalists under parental supervision.

However, what would happen if humans were to disappear before all nonhuman sentient creatures are sterilized? An enormous number of nonhuman sentient creatures would have to suffer excruciating pain for a very long time before the natural extinction of all nonhuman sentient creatures occurs. It would be human selfishness to choose self-extinction while leaving animals in great pain for a long time, because the amount of pain antinatalists would have to endure would be much less than that of all the nonhuman sentient creatures that would survive human extinction. We should not choose to eliminate a smaller amount of pain when there is a significant gap between the two. Therefore, again, the answer should be the survival of a small number of antinatalists through their own procreation for the purpose of putting an end to the procreation of a large number of other sentient creatures.Footnote ²³

Phase three: Until the extinction of all nonhuman creatures

The extinction of all sentient creatures is not the final goal of sentiocentric antinatalism. When Phase Two is completed, the beings that remain on the earth will be a small number of antinatalists and a large number of nonsentient creatures. Here arises the problem of the possibility of nonsentient creatures evolving into sentient creatures after the extinction of all human beings. If such evolution occurs, the earth will again be covered with a huge number of sentient creatures that will suffer from the evil of procreation. Therefore, this possibility should be prevented at all costs. The only beings who can prevent it are antinatalists.

Häyry and Sukenick also mention the possibility of evolution. They say that if sentient creatures were exterminated but nonsentient creatures were left untouched, “[n]onsentient entities, including plants and bacteria, may survive, unless they are seen to be a threat. Left behind, they could, in time, once again develop sentience, and the chain of suffering would remain unbroken … .”Footnote ²⁴ The problem of the unpredictable evolution of nonsentient creatures is not the discovery of Häyry and Sukenick. It was discussed in a debate on negative utilitarianism by Ninian Smart and J. W. N. Watkins. Negative utilitarianism raises the argument that if the elimination of pain is the most important thing for humans, then the instantaneous, painless killing of the entire human species with weapons would be the best solution.Footnote ²⁵ However, even if humans could instantly destroy all creatures, including themselves, there would still be the possibility of the evolution of life from the lifeless environment.Footnote ²⁶ I return to this topic in the next section.

If we take the possibility of evolution seriously, the remaining alternatives are either to sterilize all nonsentient creatures or to destroy all nonsentient creatures. Sterilizing all nonsentient creatures on earth would be meaningless because the problem is not the procreation of nonsentient creatures (their coming into being does not involve the evil of bringing pain) but the existence of nonsentient creatures (that have the potential to become sentient creatures through evolution). Therefore, sentiocentric antinatalists’ strategy should be to destroy all nonsentient creatures using chemical or biological technologies. Of course, destroying all nonsentient creatures would mean losing all trees, all flowers, all plants, all insects, and all jellyfish, and this would cause many antinatalists great pain and suffering on the psychological level: they would never experience four beautiful seasons or natural scenery. However, sentiocentric antinatalists would think that, compared to the enormous pain that sentient creatures have experienced so far—and would experience if they were to be born through evolution in the future—the pain of antinatalists caused by procreation would be significantly less and should be endured with all their strength.

Please note that the sentiocentric antinatalism discussed here is not the same as the antinatalism that argues that all creatures must be exterminated because the biological way of life is categorically wrong. While the former thinks that all living creatures must be exterminated because the existence of creatures leads to the evolution of sentience, the latter thinks that the existence of creatures is itself bad and that they must be removed from the universe.Footnote ²⁷

In Phase Three, the obligation of sentiocentric antinatalists is to survive until the extinction of all nonsentient creatures on earth. This is sentiocentric antinatalists’ third obligation to survive. Here is a further modified paradox: in order to put an end to the emergence of sentient creatures, sentiocentric antinatalists must survive until the extinction of all nonsentient creatures. This is the third stage of the paradox of antinatalism, where the paradox comes much closer to its complete form.

In any case, sentiocentric antinatalists must follow the path in which they make it their greatest concern to successfully pass on their mission from generation to generation, and in which they endure the sorrow of the birth of their children caused by their own intentional act of procreation for their ultimate purpose. This is like the path of religious practitioners.

Phase four: Endless monitoring for prevention

The discussion does not end here. Sentiocentric antinatalists must survive the extinction of all nonsentient creatures. That is, if sentiocentric antinatalists stopped procreating and became extinct, there would arise the possibility that on the surface of the lifeless earth’s soil or on the ocean floor, a new life form might begin to evolve from inorganic materials in a manner similar to the birth of life on earth some four billion years ago. If the human species died out, no one could stop this process from happening.

J. W. N. Watkins writes about the possibility of the evolution of life after the instantaneous killing of all creatures on earth, in the context of negative utilitarianism, as follows:

As Watkins points out, it is impossible for humans to destroy the possibility of the emergence of new life forms from the inorganic world. Therefore, antinatalists can only monitor the risk of their emergence and, if they find something dubious, destroy it immediately.

For this reason, sentiocentric antinatalists must survive the extinction of all nonsentient creatures and continue to monitor the situation on earth and nearby celestial bodies. In Phase Four, their efforts shift from extermination to monitoring.

Sentiocentric antinatalists must give birth to children and pass on their mission to them. In the future, the lifespan of an antinatalist might be greatly extended almost to immortality, as Phil Torres arguesFootnote ²⁹; but even if that were true, antinatalists would still have to give birth to future generations in case many of them died from unpredictable accidents. This kind of infinite monitoring of the earth and accessible celestial bodies to prevent the emergence of new life forms becomes sentiocentric antinatalists’ fourth obligation to survive.Footnote ³⁰ Here is found the final version of the paradox: sentiocentric antinatalists must survive indefinitely in order to prevent the emergence of life. This is the fourth stage of the paradox of antinatalism, which is its complete form.

Readers may wonder if there is not a way to leave the monitoring operations to an automation mechanism supported by artificial intelligence. It may be possible. In this situation, antinatalists would have to be prepared for cases in which major failures or malfunctions suddenly occur in the system; if such a thing happened, antinatalists would have to rush to the center of the control room and repair the entire system.Footnote ³¹

Now it is clear that antinatalists must do three kinds of monitoring: monitoring the emergence of life forms, monitoring their own technological systems, and monitoring the smooth transfer of their mission to future generations. These are all obligations that antinatalists would have to bear on a lifeless future earth. Monitoring and prevention: this is the work that antinatalists must continue indefinitely.

What would happen if antinatalists disappeared from the earth due to a serious accident? There is a possibility that new life forms could emerge on earth or on other nearby planets and evolve into sentient creatures. There is also the possibility that at the end of a long evolutionary process, an intelligent species like humans could emerge, and there may be antinatalists among this species. If they began to persuade their comrades, a similar process would begin again. This would be an eternal struggle between antinatalism and biological evolution. This suggests that the most fundamental enemy of antinatalism is the power of eros or Werden, which is always trying to revive itself again and again from the world of death and nothingness. This is the endpoint to which our philosophical exploration leads.

Understanding all these things, accepting the obligations of survival, and carrying them out with sincerity thus become the ultimate meaning of life for sentiocentric antinatalists. Even if there is pain caused by a chain of procreation, sentiocentric antinatalists can be compensated by their ultimate meaning of life: that by their sincere devotion to monitoring and prevention through generations, the future possibility of the emergence of enormous pain in the world will be prevented.

Sentiocentric antinatalists would be extremely lonely in Phase Four. The earth’s biological ecosystem would already be extinct, they would not see any traces of life near the earth, and there would be no god anywhere to speak holy words to them. They would have to live their lives torn between their obligation to fulfil their mission and their existential anxiety. This journey would go on indefinitely. However, they would be happy because their ultimate goal would be very clear, and they could find life’s meaning in their endless effort to monitor and prevent the emergence of new life forms in the world.

Some discussions and conclusion

From the discussions in the previous sections, it is clear that the paradox of antinatalism in its complete form is that in order to put an end to all births of sentient creatures, including human beings, and to continue to prevent the emergence of sentient creatures as a result of evolution, sentiocentric antinatalists must continue to give birth to their children indefinitely, passing on their mission to their children for the purpose of achieving the goal of their antinatalism. In short, the paradox is that in order to stop all procreation, they have to keep procreating.

It is very important to clarify the essence of the paradox of antinatalism. What kind of paradox is it?

It is not a logical paradox, which would contain an inconsistency in its proposition. It is a performative paradox, or a performative contradiction, which arises when a person tries to act according to a certain principle in which she believes. In other words, it is a paradox that occurs in such a way that the result of an act inevitably leads to the negation of the purpose of the act.Footnote ³² This is because in sentiocentric antinatalism, the result of an act, which is the infinite survival of antinatalists, inevitably leads to the negation of the purpose of the act, which is the prevention of the procreation of all sentient creatures, including humans. One reason for such a paradox occurring is that there is a possibility of biological evolution in this universe. If there were no such possibility, the paradox of antinatalism would not occur. Therefore, this is a kind of paradox in which the result of an act inevitably negates the purpose of the act due to the fact that a certain possibility or tendency is strongly built into the world.

Interestingly, the paradox of antinatalism is similar in structure to the paradox of time travel—especially the case of going back in time to kill one’s grandparent. David Lewis explores this type of paradox in his 1976 paper on time travel. A man named Tim travels back in time using a time machine and tries to kill his grandfather. However, he cannot kill his grandfather because every time he tries, unpredictable disturbances occur; for instance, “some noise distracts him at the last moment” or “he even feels a pang of unaccustomed mercy.” Due to such unlucky happenings, his act of killing inevitably fails. Of course, the fundamental reason for the impossibility is that if the killing were to happen, it would annihilate the cause of Tim’s very existence.Footnote ³³

In the above case of time travel, the result of Tim’s action, which is the impossibility of killing his grandfather, also inevitably leads to the negation of the purpose of the act, which is the killing of his grandfather. Tim is able to go back in time with a time machine, finds his grandfather standing there, has practiced shooting beforehand, and has the physical fitness to accomplish his task, but each time, unpredictable happenings occur and interfere with his shooting. One reason this happens is that there is a strong cause-and-effect relationship in the world, and past causes necessarily affect subsequent events. If there were no such relationships in the world, there would be no paradox of time travel. This is the same structure as is found in the paradox of antinatalism.

However, there is a small difference between them. While in the case of time travel the impossibility of killing is categorically determined, in the case of antinatalism, the possibility of the perfect nonemergence of sentient creatures after sentiocentric antinatalists give up their procreation can still theoretically exist. In this sense, the paradox of antinatalism is weaker than the paradox of time travel. However, the paradox of antinatalism has a unique structure that cannot be reduced to that of time travel.

Readers might feel that the paradox of sentiocentric antinatalism is merely an unoriginal instance of a broader paradox: that the effective reduction of harm caused by a certain action may require maintaining that very action on a small and limited scale. Consider the case of drug control. If a society overregulates drug use, many heavy users may turn to black markets, worsening the social environment and, in the long run, causing a significant decline in social security and public health. One alternative to prevent such a scenario is to provide supervised drug injection services for heavy users, operated by NGOs or public institutions, thereby containing the negative effects of drug use within a socially manageable threshold. This is a typical example of the paradox described above. Similar patterns can be observed in the case of prostitution.

One of the most striking differences between the case of drug use and that of sentiocentric antinatalism is that, in the former, the party seeking to reduce the harm caused by drug use in society is entirely distinct from the party permitted to use drugs under the supervision of specialists. In contrast, in sentiocentric antinatalism, the party attempting to reduce the harm caused by procreation is the very same party that deliberately forces themselves to bring children into existence in order to prevent the emergence of future sentient creatures. This indicates that the paradox of sentiocentric antinatalism is not merely a straightforward application of the above paradoxical structure to procreation, but rather a unique case that may involve a distinct paradoxical structure. The author intends to explore this uniqueness in greater depth in future philosophical research.

This discussion now concerns obligations.

The obligations described in Phases One through Four are those that sentiocentric antinatalists impose on themselves based on the principles of pain-emergence preventism and antispeciesism. There is a kind of human dignity in the fact that people can continue to live according to the moral principle they have established, even if that principle causes them great harm that they would rather avoid. There is also sorrow in that as long as people try to eliminate pain from all sentient creatures in a coherent way, they can never escape the pain that is to be imposed on themselves by their very pursuit of such actions.

There may be antinatalists who wonder why they should have an obligation to think seriously about the pain of other sentient creatures. They may think that it is not wrong to prioritize the happiness of the existing human species over the actual or potential pain of nonhuman creatures. Here, I would like to introduce the idea of supererogation and further discuss the meaning of obligation for antinatalists because this topic is closely related to classical philosophical debates on obligation and supererogation.

A supererogatory action is one that goes beyond the upper limit of required obligations. In other words, it is an action that one does not normally have to do, but that makes one more praiseworthy if done. Alfred Archerd and Michael Ridge state that “[s]upererogatory acts are those that are beyond the call of duty.”Footnote ³⁴

We can imagine a kind of antinatalism that strongly imposes on antinatalists the obligation to survive for the purpose of human extinction, but loosely recommends, as a praiseworthy action, survival for the purpose of preventing the emergence of sentient creatures. Such antinatalism regards collective anthropocentric action by antinatalists as their obligation and collective sentiocentric action by antinatalists as their supererogatory action. I call this “quasi-anthropocentric antinatalism.” The difference between anthropocentric antinatalism and quasi-anthropocentric antinatalism is that the latter regards the human species’ attempts to survive for the purpose of preventing the emergence of sentient creatures as supererogatory and praiseworthy, whereas the former never regards them as supererogatory or praiseworthy.

However, our sentiocentric antinatalism is quite different from the above two.

Let us consider the nature of sentiocentric antinatalism from the viewpoint of obligation and supererogation. It is interesting that sentiocentric antinatalism views human obligation in a completely different way than anthropocentric antinatalism or quasi-anthropocentric antinatalism. While anthropocentric antinatalism and quasi-anthropocentric antinatalism regard human extinction as our strict obligation, sentiocentric antinatalism never proposes this, because, according to its principle, the human species must survive indefinitely in order to prevent the emergence of creatures. It is a startling discovery that human extinction cannot be the strict obligation for sentiocentric antinatalists. Then what is the strict obligation for sentiocentric antinatalists? The answer is clear: indefinite survival for the purpose of exterminating sentient creatures (except the antinatalists themselves) and monitoring for symptoms of the emergence of living creatures.

In the case of sentiocentric antinatalism, while its principle is the equal extinction of all sentient creatures, including the human species, its actual result is the prioritization of the extinction of all nonhuman creatures over that of the human species.

What then is the supererogatory action for sentiocentric antinatalists? My answer is that fully accepting the paradox of antinatalism and proudly affirming the fact that they are doing the opposite of what they originally intended constitutes supererogatory action for sentiocentric antinatalists. This is because even without such inner acceptance and affirmation, they can accomplish their indefinite survival and pursue their ultimate obligation, but accomplishing it with inner acceptance and affirmation will add supererogatory value and beauty to their accomplishment and make it more consistent, praiseworthy, and meaningful. In this supererogatory part, sentiocentric antinatalism is similar to rigorous stoicism, which is very difficult to accomplish, but would be very praiseworthy if it could be realized. This shows that the essence of sentiocentric antinatalism is highly religious, which can be considered in line with ancient asceticism. I believe that research from the perspective of philosophy of religion will be most fruitful in exploring the central core of sentiocentric antinatalism, even though almost no sentiocentric antinatalist would consider themselves to be religious.

Readers may think that if sentiocentric antinatalism inevitably contains a serious paradox, it should be abolished, but I do not think so. I believe that sentiocentric antinatalism can be established as a philosophical, stoic, and ascetic movement that contains an insoluble paradox at its core. The presence of a paradox does not necessarily constitute a reason to demolish an idea. For example, there is a huge paradox in Kant’s epistemology that the Ding an Sich must exist as the source of our perception, while we can never perceive it directly. This paradox does not necessarily mean that Kant’s framework should be abolished. Rather, philosophers need to investigate why such a paradox inevitably arises when we think philosophically about the structure of our perception. The same applies to the paradox of antinatalism. What we need to do is not abolish sentiocentric antinatalism, but rather investigate why this kind of paradox inevitably arises when we think about the universal prevention of the emergence of pain. The important thing is to clarify the structure of the paradox and to examine it theoretically.

It is true that many antinatalists do not have such an extreme idea about the fates of humanity and living creatures. They are attempting what they can actually accomplish in a given situation. If I were an antinatalist, such an extreme conceptual analysis would feel annoying and frustrating. However, I do not think that the philosophical analysis made in this paper is meaningless. My argument should have its own significance, and even frustrated antinatalists will be able to use it as a conceptual tool to rethink the strengths and weaknesses of their ideas and actions.

I hope that this philosophical investigation will contribute to fruitful discussions in the fields of antinatalism and the philosophy of life’s meaning.