1. The Less Bad Theory

The theory of population ethics I advance can be summed up in the following formula:

I shall now unpack this formula step by step, beginning with some brief terminological remarks about my use of “good” and “bad”. “Good” refers to what is good for individuals. This includes all the positive constituents of well-being. According to hedonism, pleasure is the only positive constituent of well-being. “Bad” refers to what is bad for individuals.Footnote ³ This includes all the negative constituents of well-being. The positive and negative constituents of well-being are weighed against each other in the balance of well-being. When the negative constituents of well-being outweigh the positive ones, an individual has overall negative well-being. According to hedonism, for example, this is the case when the pains in a person's life outweigh the pleasures.

The concept of bad I employ includes what, drawing on Jeff McMahan (Reference McMahan2002: 145–165), we can call a being's lifetime misfortune or misfortune for short. Individuals suffer a misfortune to the extent that their life falls short of its potential, that is, short of what the life as a whole could have been – be it because the life would have been of a higher quality for the time it actually lasted or because it would have lasted longer and contained additional goods.

We can illustrate the concept of misfortune by considering a person who suffers an incurable cognitive impairment after a car accident at the age of five (see McMahan Reference McMahan2002: 325). Assume that this impairment greatly reduces the person's well-being by limiting the range of activities she can engage in and the pleasures she can enjoy to those of a contented dog.Footnote ⁴ Given the life she could have led, this would amount to a great misfortune for that person: her well-being will fall far short of what it could have been. For a dog, on the other hand, living with the cognitive limitations of a dog is not a great misfortune, given that the dog's well-being potential is much lower.

As McMahan highlights, the notion of misfortune concerns how a life is going for an individual – whether or not the individual experiences the misfortune. For example, the severe brain damage “may not be dreadful experientially – that is, it may not be dreadful because of the subjective character of the individual's experiences – but it is dreadful nonetheless for this individual” (McMahan Reference McMahan2002: 325).

2. Explaining the procreation asymmetry and the non-identity problem

Here is how the Less Bad Theory explains the procreation asymmetry. There are moral reasons not to create lives that are not worth living because there are moral reasons to prevent the bad. By contrast, there are no moral reasons to create lives worth living because there are no moral reasons to promote the good.

This explanation is similar to the complaint-based approach in that both agree that morality does not aim at promoting the good, but at avoiding something negative. In the case of the Less Bad Theory, however, this negative thing does not consist in complaints, but in all that is bad for individuals, including the misfortune of unrealized potential.

This difference allows the Less Bad Theory to solve the non-identity problem as follows. Suppose that you could either create a person who lives a good life but dies at the age of thirty, or a person who lives a much better life and dies at the age of seventy. Let us assume, for simplicity, that neither life contains any pain or other bad things. The gross lifetime well-being is made up of purely positive constituents. Nevertheless, it is clear that the life of thirty years is more unfortunate than the better life of seventy years: the life of thirty years fulfils the human potential for gross well-being to a lesser extent. Therefore, the Less Bad Theory recommends creating the better life.

This solution to the non-identity problem avoids the pitfalls of the complaint-based approach. The complaint-based approach relied on comparing how a person would fare in one choice option to how she would have fared in the alternative choice option. Hence, it arrives at the conclusion that the thirty-year-old would have no complaint if one created her. In contrast, the misfortune of unfulfilled potential is evaluated relative to the potential of the kind to which the individual belongs.Footnote ¹³ There is a reason not to create the worse-off human because she will be burdened with more unfulfilled potential, relative to some norm potential that equally applies to all human welfare subjects. In other words, there is a reason not to create the life of thirty years because this life would be worse relative to how good a human life could be.

It might be helpful to compare the Less Bad Theory with two related accounts of the non-identity problem: Elizabeth Harman's (Reference Harman2004, Reference Harman, Roberts and Wasserman2009) and Molly Gardner's (Reference Gardner2015) harm-based approaches. Roughly speaking, Harman argues that it is prima facie wrong to cause harm. One causes harm if one causes a person to be in a bad state. Bad states are states that are “worse in some way than the normal healthy state for a member of one's species” (Reference Harman, Roberts and Wasserman2009: 139).Footnote ¹⁴

An example helps to show that there are important structural differences between Harman's approach and the Less Bad Theory. Suppose you are faced with the choice of creating one of two people. Both would live for fifty years in a normal, healthy state, and not in a bad state. However, one of them will enjoy a much higher level of well-being than the other. Harman's harm-based considerations do not imply that there is a reason to create the better life.

In contrast, the Less Bad Theory implies that there are reasons not to create the worse life because of some additional misfortune. An individual's misfortune is evaluated not in comparison to the baseline of a normal, healthy state, but in comparison to all possible better gross lifetime well-being levels that members of a kind could reach. The reason not to create the worse life would therefore be that it is burdened with the additional, if only minor, misfortune of not fulfilling its potential to the extent that the better life does.

Gardner (Reference Gardner2015) has proposed a related harm-based account of the non-identity problem. Very roughly, there are moral reasons not to cause harm, and a state of affairs is a harm for an individual if and only if the individual is worse off in some respect than it would have been had the individual existed but the state of affairs had not obtained. Similar to the considerations of probability presented above, Gardner argues that the more inevitable the harm, the less weighty are our reasons not to cause it.

However, Gardner considers how inevitable a harm is for a particular individual (441). Therefore, her account runs into a problem that the Less Bad Theory avoids. Suppose you are faced with the choice of creating a severely impaired child with extremely limited well-being but also very limited individual potential for well-being, or a child with a very good life but with a potential for well-being far surpassing that high well-being level. Let us assume that the possibility of curing the impairment is extremely remote. Moreover, the possibility of creating the same child without the impairment is likewise extremely remote. Had one modified the genome to avoid the impairment, for example, a different child would have come into existence instead. For the impaired individual, then, the harm is almost inevitable. Therefore, on Gardner's view, the harm has correspondingly little moral weight. Conversely, if the probability that the better life could have been even better is very high because of an enormous individual potential, the better life involves a harm that has greater moral weight. Gardner's approach would conclude that, as far as harm is concerned, it is preferable to create the human who is worse off. As the Less Bad Theory measures the potential by reference to the individual's kind, it avoids problems of this sort.

Gardner might, however, reply that one has an overall moral reason to create the better-off child because one also has a reason to benefit people in the sense of causing them to exist and have good lives. Even if this reply goes through, however, it commits Gardner to denying the procreation asymmetry.

Indeed, both Harman (Reference Harman2004: 97–98) and Gardner (Reference Gardner2016: 327–332) endorse the view that there are reasons to benefit people by causing them to exist and have happy lives. Accordingly, Harman also has a way to argue that there is a pro tanto moral reason to create the person with higher well-being even if neither person is more greatly harmed relative to the baseline of a normal, healthy state. While this might allow Harman to offer a more comprehensive treatment of non-identity cases, the emerging theory fails to account for the procreation asymmetry.

The Less Bad Theory, by contrast, denies that there are any reasons to promote the good or benefit people. Instead, there are only reasons to prevent the bad, including the misfortune of unfulfilled potential. If the Less Bad Theory recommends benefitting people, that is only because benefitting people reduces the bad. In this way, the Less Bad Theory can account for both the procreation asymmetry and the non-identity problem.

3. Crabs and humans

In addition, the Less Bad Theory allows us to deal with non-identity cases involving both human and non-human animals. Suppose you could create a thousand ordinary crabs. They live for about four years; their lives consist of mild bodily pleasure. Alternatively, one could create a thousand human beings who live crab lives. Same length, same content. They experience neither friendship nor love, explore neither the world nor their innermost selves; they are left with nothing but the occasional pleasure of crabs. It is plausible to suppose that we have a moral reason not to create the humans who are confined to the state of crabs. Yet textbook utilitarianism, for example, cannot accommodate this view, for it claims that the only thing that matters is increasing the total balance of pleasure over pain in the world. This balance is the same in either case.

Under the assumption that there is a moral reason to avoid unfulfilled potential, a simple and intuitive explanation emerges. The crabs almost completely fulfil their potential as crabs. Humans living crab lives, on the other hand, fall very short of what is possible for humans. This misfortune is a morally significant difference between creating a crab living a crab life and a human living a crab life. The Less Bad Theory takes that difference into account.

Next, consider the choice between creating a flourishing human being and a flourishing cat. There does not seem to be any moral reason to create the human rather than the cat (Boonin Reference Boonin2014: 205–206). Textbook utilitarianism fails to account for this intuition. It recommends creating the human life since it contains more well-being, due to being longer and richer. The Less Bad Theory, by contrast, can explain why nothing speaks against creating the cat: the great surplus of goodness of the human life with respect to the cat life generates no moral reason to create the human because there is no moral reason to promote the good or to benefit individuals.

Moreover, the Less Bad Theory is slightly better equipped to solve this problem than the accounts of Gardner and Harman.Footnote ¹⁵ Both hold that there are moral reasons to benefit people in the sense of causing them to exist and to have good lives. On such views, there would be at least some moral reason to create the human rather than the cat. However, there seems to be no such reason at all. The Less Bad Theory explains why.

4. Objections

One might object that the Less Bad Theory has antinatalist implications. If there is a pro tanto moral reason to prevent the bad, then there is a pro tanto moral reason not to create a normal good life burdened by some bad things. This reason, it seems, lacks a counterweight, given the assumption that there are no reasons to promote the good. As long as we abstract from any positive effects on other people, the Less Bad Theory seems to imply that the balance of moral reasons is against creating an ordinary good life (see Frick Reference Frick2014: 130–131).

This objection is based on the additive fallacy (Kagan Reference Kagan1988). According to the underlying picture, the good can justify the bad only if it exerts a normative force in the opposite direction, towards bringing about an outcome – as if the only means to prevent a frightened dog from running away were to tie it to an enthusiastic dog running in the opposite direction. We can reject this limited picture of moral factors. Goodness need not act as an attractive force that pulls us towards bringing something about. As McMahan (Reference McMahan, Roberts and Wasserman2009) has noted, one can avoid antinatalism by assuming that the good has a justifying function without having a reason-giving function: it can justify the bad without exerting an attractive force.Footnote ¹⁶ A lamppost can keep a dog from running away without having to move in the opposite direction.

According to McMahan (Reference McMahan, Roberts and Wasserman2009: 54), it would be “strikingly ad hoc” to claim that the good has merely a justifying function with respect to procreative decisions, while maintaining that it has a reason-giving function in other cases, for example when only already existing people are involved. The Less Bad Theory circumvents this problem. Rather than claiming that the good sometimes has a moral reason-giving function, the theory says that the good only ever has a justifying function.Footnote ¹⁷

One might object that instead of the Less Bad Theory, one should adopt a view according to which there is a very weak reason to create happy people. Just like the Less Bad Theory, this view avoids the untenable implication of total utilitarianism that there are strong moral reasons to create happy people. But it also avoids the gap between the justifying and the reason-giving functions of the good.

In fact, however, the most plausible variants of this view likewise imply such a gap. The gap can only be closed if one assumes that the reason-giving function of the good is equally strong as its justifying function. Total utilitarianism closes the gap at the cost of the implication that there is a strong reason to create happy people. On the premise that there is only a very weak reason to create happy people, one can only close the gap by assuming that the justifying function of the good is also very weak. But this has untenable implications, too. There would be a counterintuitive reason not to create certain very good lives in which there is considerably more good than bad. Due to its weak justifying function, the good could not justify the bad. The most plausible variants of the view that there is a weak reason to create happy people, then, will hold that the justifying function is stronger than the weak reason-giving function. There is a gap either way.

One further objection might be that the Less Bad Theory violates the principle of choice-set independence (see Greaves Reference Greaves2017: 11). According to this principle, the relative preference ranking of two choice options A and B cannot depend on which alternative options are available. To illustrate, consider a case in which there is a choice between creating an overall good life of thirty happy years and creating no life. Assume, for simplicity, that the created person's gross well-being would not have any negative constituents. This gross well-being is so considerable that it would not be outweighed by the badness of unfulfilled potential. In this case, no option – neither (A) creating the life, nor (B) creating none – seems morally preferable to the other.

But now suppose that you could, as a third option, create an even better life of seventy years. This person's gross well-being, which would likewise have no negative constituents, would be much larger; the misfortune of unfulfilled potential would be correspondingly smaller. In this three-option choice, it seems that while there is no moral reason to create the life of seventy years rather than none, there is a strong reason not to create the life of only thirty years. Thus, (A) creating the life of thirty happy years now seems morally inferior to (B) not creating any life at all.

In reply, one can argue, following Parfit (Reference Parfit1981: 131–133), that other common-sense judgments likewise violate choice-set independence. For instance, assume that you could, at a high cost to yourself, prevent a miserable life full of terrible and uncompensated suffering from being created. Even if the cost to you is smaller than the suffering you would prevent, it justifies not preventing the life from coming into existence. Consequently, both options are permissible. But now consider a choice between doing nothing, preventing one miserable life from coming into existence at a high cost, or preventing the existence of the same child and that of the second child at the same high cost. Again, given the high cost to yourself, not preventing the existence of either child is justifiable. Paying the cost but preventing only one child from suffering, however, would not be justified; it would be morally perverse.Footnote ¹⁸

Violations of choice-set independence can be explained by appealing to the moral relevance of choice-set dependent properties (Dietrich and List Reference Dietrich and List2017: 447–449). Choice-set dependent properties are properties that are not intrinsic to the options but instead depend on which other options are available. In the case of the children, for example, one might argue that an option is unjustified with respect to another if the other option contains the same sacrifice but less badness. Using a sacrifice to prevent some limited bad is unjustified if the same sacrifice could be put to a greater protective use. Therefore, making the sacrifice but only saving one child is unjustified with respect to the alternative of saving both. As a consequence, it is unjustified full stop.Footnote ¹⁹ By contrast, because the option of not saving any child does not contain any sacrifice, it is not unjustified with respect to the alternative of saving both children.

Likewise, the violation of choice-set independence by the Less Bad Theory can be explained by the following context-dependent principle of justification:

This principle can explain why creating the shorter life is morally inferior in the three-option choice: the alternative of creating the life of seventy years contains less bad while containing at least as much good. By contrast, if we are faced with the limited choice of creating no life at all or the life of thirty happy years, there is no such alternative.

The principle allows us to handle the simple case in which the alternative life contains at least as much good and less bad. However, the better life might be burdened with greater badness than the worse life. This might be the case when the better life is much more turbulent than the worse life, fluctuating between great and terrible times. Although the turbulent life contains more bad things than the steady life, it is better overall because it also contains much greater goods.

The principle cannot be applied directly to a choice between a better turbulent life and a worse but steady life. Further principles would need to be determined. One could, for example, argue for the following. The turbulent life is equivalent to a life that contains as much good but less bad than the alternative option, the worse but steady life. Via this equivalence, one can treat the choice like the corresponding simple case.

Some will think that creating a turbulent human life is equivalent to creating any other human life at the same gross well-being level. If this were true, we could treat all human lives as if their gross well-being were made up of purely positive constituents, so that all that would be bad for these individuals would be their unfulfilled potential. On the resulting view, creating human lives with higher overall well-being – whether turbulent or not – will always be preferable to creating human lives with less well-being.

Following Elizabeth Harman (Reference Harman2004: 99), however, one might argue that the turbulence of a life may well make a moral difference. Imagine you could create a life that achieves a very high level of lifetime well-being. However, at some point in that life, the person will suffer a terrible illness and several years of agonizing pain. Suppose you could also create a fairly good life that is slightly worse than the first but, on the other hand, contains only mild pain and no other significant bad things. On Harman's view, it would be preferable in such a case to create the overall worse life, given the terrible pain that the better life contains.

I do not commit myself to the view that it would be preferable to create the worse life in this case. Still, I agree with Harman insofar as I have no strong intuition that it is morally preferable, in this case, to create the better life. By contrast, the canonical cases of the non-identity problem do evoke strong intuitions. In one of these canonical cases, a girl is faced with the decision to either have a child at the age of fourteen, whom she would give a bad start in life, or to become a parent later and give a non-identical child a better start in life (Parfit Reference Parfit1984: 358). Another canonical case compares future generations of the same size living under different conditions. In one option, the future people live much better lives because climate change or resource depletion was prevented. In the alternative option, no such measures get taken, and the non-identical future people who come into existence have lives that are still worth living but far worse (361–362). These cases elicit strong intuitions that it is morally preferable to create the better lives.

Given the strength of our intuitions concerning such examples, our judgments about these cases are the fixed points that a moral theory must address. The descriptions of these cases suggest that the better lives are also the lives that contain less bad. The proposed principle allows us to accommodate these fixed points. Further refinements might be the subject of future work.