Nonidentity Problem

The International Encyclopedia of Ethics. Edited by Hugh LaFollette, print pages 3634–3641.

© 2013 Blackwell Publishing Ltd. Published 2013 by Blackwell Publishing Ltd.

DOI: 10.1002/ 9781444367072.wbiee314

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Nonidentity ProblemMelinda A. Roberts

The Nonidentity Problem and the Person-Affecting Intuition

The nonidentity problem is widely considered to challenge the person-affecting

intuition. According to that intuition, an act can be wrong only if that act harms, or

will or can be expected to harm, some person. “What is bad must be bad for someone”

(Parfit 1987: 363).

The nonidentity problem arises when we realize that many apparently wrong,

future-directed acts – that is, acts whose undesirable effects are to be exclusively

imposed on people who do not yet exist – seem to harm, or make things worse for,

no one at all. The problem we are left with is that of explaining how acts that harm

no one can be wrong.

At the core of the problem is the point that the undesirable condition that the act

under scrutiny imposes seems not itself to be a harm – or at least that it does not

seem to be a harm in any “morally relevant sense” (Parfit 1987: 374). The idea is this.

The person we may at first consider the most obvious victim of the wrong act on

closer inspection seems unable to exist at all in the absence of the undesirable condi-

tion. Yet, that person’s life is – we are to suppose – clearly worth living. How then has

that person been harmed – any more than the child has been harmed who suffers

the sting of the needle when being vaccinated against – say – tetanus (Parfit 1976;

Schwartz 1978; Adams 1979)?

In any particular instance of the nonidentity problem, the claim that the future life

critically depends on the prior wrong choice is itself, of course, in need of argument.

In most cases, the argument for that claim is best appreciated by thinking through the

case from an after-the-fact perspective. Thus, suppose that agents in fact choose to

deplete important resources when they might have chosen to conserve them instead

(Parfit 1987: 361–4). And suppose that a child, Harry, is born a few generations later

into an undesirable condition – the condition, say, of clean water being in short supply.

We then ask what the choice of conservation in place of depletion – the choice, that is,

that would have avoided that undesirable condition – would have meant for Harry.

A correct answer to this question must take into account the phenomenon Kavka

called the “precariousness” of the coming into existence of any particular person

(1981: 93). Parfit details that phenomenon as follows:

Suppose that we are choosing between two … policies [and that under one] the

standard of living would be slightly higher over the next century. That effect implies

another. It is not true that, whichever policy we choose, the same particular people will

exist. … Given the effects of two such policies on the details of our lives, it would

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increasingly over time be true that … people married different people. And, even in

the same marriages, the children would increasingly over time be conceived at different

times. … Since the choice between our two policies would affect the timing of later

conceptions, some of the people who are later born would owe their existence to

our choice. … And the proportion of those later born who owe their existence to our

choice would, like ripples in a pool, steadily grow. (1987: 361)

In other words: the effect for Harry of conservation in place of depletion would not

have been a better existence but rather no existence at all. Or, at least, very probably,

the effect for Harry of conservation in place of depletion would have been no exist-

ence at all. Of course, any alternate person brought into existence in place of Harry

may well be better off than Harry in fact is. After all, that person will inhabit a world

where clean water is abundant. However, bringing any better-off but nonidentical

person into existence in place of Harry does Harry no good at all.

It then begins to look like the choice of depletion is, all things considered, not the

choice that makes things worse for Harry – the choice that harms Harry in a morally

relevant sense – but rather, if anything, the choice that benefits Harry. Depletion has

brought him into an existence worth having when he otherwise would – at least very

probably – never have existed at all.

Yet, we continue to think that the choice of depletion is wrong, depending on

details of the case (which details may include, e.g., that relatively few existing people

are benefited by depletion, while many future people are made to suffer). The upshot

is that, according to the nonidentity problem, we must reject the person-affecting

intuition. We must instead understand that some “bad” acts are “bad for” no one at

all. However, we do not thereby solve the problem since – as Parfit argues – we now

face a further challenge: the challenge of providing a plausible account of why the act

that will predictably make things worse for no one is nonetheless wrong.

Many other instances of the nonidentity problem seem to work in the same general

way as the depletion case does. These include Parfit’s risky policy case (1987: 371–4),

Kavka’s slave child and pleasure pill cases (1981: 93–112), and the Acme chemical

company case (Woodward 1986: 813–14; Smolkin 1999: 195; see climate change).

The person-affecting intuition is sometimes formulated in a way that focuses, not

on the evaluation of acts for their permissibility (Parfit 1987: 363), but rather the

evaluation of outcomes, or possible futures or worlds, in terms of their overall better-

ness (Parfit 1987: 370). On that alternate formulation, we would say that a world X is

morally worse than Y only if X makes things worse for some person who does or will

exist in X than Y (or we might instead want to say: than some Z) makes things for

that person. Whether we are interested in the deontic or the telic version of the

intuition, however, the choice of X is not to be judged wrong – or, alternately, X is

not to be judged worse than Y – in the case where the only (arguably) bad thing

about the choice of X – or X itself – is that it leaves a well-off person out of existence

altogether. For in that case X harms – that is, makes things worse for – at most a

person who is merely possible relative to X and not for any person who does or will

exist in X.

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The details of formulation are critical. If, for example, the person-affecting

intuition is rewritten as a sufficient condition on when the choice of X is wrong – or

when X is worse than Y – then the resulting principle may well (depending on how

that work is done) seem implausible. For example, the principle that an act is wrong

if it is worse for a person who does or will exist under that act and better for no per-

son who does or will exist under that act seems clearly unacceptable (Parfit 1987:

395–6; Hare 2007: 501–11; Roberts 2010: 64–74; Roberts 2011; see population).

For different reasons, so is the principle which asserts that bringing an additional

well-off person into existence cannot make things either better or worse (Broome

2004: 143–8; 2009). However, even the most cautious formulation of the person-

affecting intuition leaves the intuition vulnerable to the nonidentity problem.

The Import of the Problem

The nonidentity problem is important because the person-affecting intuition is

important. Of course, that the person-affecting intuition is false will come as no

surprise to many nonconsequentialists. Rights-theorists, for example, may well be

convinced in advance of any discussion of the nonidentity problem that violating a

person’s rights can make things better for that person but still be wrong.

Accordingly, to appreciate the import of the nonidentity problem, it is useful to

view the problem as part of the debate regarding whether the basic consequentialist

idea that we ought to create the most good – that is, the most pleasure, happiness, or

well-being – that we can is at root plausible (see consequentialism). Specifically,

the theorist who finds that idea compelling may be attracted to the person-affecting

intuition as a curb on what even many consequentialists consider the excesses of the

classic utilitarian principle, or totalism (Feldman 1995: 190–3).

According to totalism, what we do is wrong when we could have created additional

well-being on a total, or aggregate, basis and fail to do so. The difficulty is that that

rule does not distinguish between two different ways in which we can fail to create

additional well-being – (1) by failing to create additional well-being for an existing or

future person, and (2) by failing to bring an additional well-off person into existence.

That the failure described in (1) often constitutes wrong-doing is a standard that

seems stringent enough. That the failure described in (2) would also constitute

wrong-doing seems to go too far. The difficulty with (2) seems especially clear when

we realize the kinds of trade-offs (2) may allow, or require, us to make. Can it really

be permissible for agents to allow an existing child’s well-being level plummet to, say,

the zero level, so long as agents have managed to offset that diminution in well-being

through the production of another child? Surely, as Narveson wrote, we “are in favor

of making people happy, but neutral about making happy people” (1976: 7).

Other Nonidentity Problems

Parfit’s depletion example is a difficult and challenging instance of the nonidentity

problem. Still another variety of the problem – one where issues involving

probabilities do not seem to be implicated in any interesting way – arises in cases in

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which impairment is due entirely to genetic or chromosomal factors. Assuming that

the impaired child’s life is worth living, and that the agents could have avoided the

impairment, we might quickly concur that the procreative choice does not harm the

child (see cloning; reproductive technology). In the law, such cases fall under

the heading of “wrongful life” (Roberts 2009b).

Parfit’s two medical programs example is a particularly important instance of the

non-probabilistic variety of nonidentity problem. Parfit’s case involves “two rare condi-

tions, J and K” (1987: 367). A woman’s having condition J will cause any child already

conceived to be impaired in a certain way. Condition K, which causes any child that the

woman then conceives to be impaired in the same way, cannot be treated but “always

disappears within two months” (1987: 367). Both conditions will affect millions of

women, but we only have enough money to implement one program – either a program

that will treat condition J, thereby making particular children better off, or a program

that will test for condition K and warn the women who are found to have it to delay

conception for two months, thereby producing nonidentical but better-off children.

Parfit asks whether there is any “moral difference” in the choice to fund one

program in place of the other (1987: 367). The person-affecting intuition sug-

gests that there is. Choosing not to implement the program that tests for and

warns of condition K is permissible since that choice does not make things worse

for any existing or future person. In contrast, choosing not to implement the

program that treats condition J does make things worse for people who do or

will exist – and a more complete person-affecting approach, though not the

person-affecting intuition itself, can be expected to imply that choosing not to

treat condition J would be wrong.

This distinction, however, may seem counterintuitive (Parfit 1987: 369). It is fair

to say that, if the “no-difference” view that Parfit endorses is correct, then we must

reject the person-affecting intuition.

Responses to the Nonidentity Problem

Some theorists have steadfastly clung to the person-affecting intuition even as they

accept the conclusion of the nonidentity argument: that is, that many apparently

wrong, future-directed acts in fact harm no one (Heyd 1992, 2009; Boonin 2008).

Such theorists take the position that, if the choice under scrutiny is wrong at all,

then it is wrong in virtue of the effects that it has on existing people or on those

future people – if any – who will come into existence however the choice under

scrutiny is made.

Many more theorists accept the conclusion of the nonidentity argument and

maintain that the problem compels us to say that a correct moral theory must be

impersonal at least in part (Parfit 1987: 378). Of course, unreconstructed totalists

will simply consider the nonidentity problem as evidence for their own view.

However, as Parfit argues, any purely aggregative approach appears to give rise to

further problems, including the Repugnant Conclusion (1987: 381–90; see also

Tännsjö 2004: 219–37; see repugnant conclusion).

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Many theorists have thus developed more restrictive impersonal approaches

(Holtug 2009: 71–92). Still others have described pluralistic approaches that would

balance the ideal of maximizing aggregate well-being against, for example, the ideals

of equality and human flourishing (Temkin 2012: 313–62; 1993: 221–7), or evaluate

our choices by reference to a combination of person-affecting and impersonal rea-

sons (McMahan 2009: 49–68; 2002: 294–338).

Still other theorists argue that the comparative (or worse off) conception of when

an act harms, or is bad for, a person is unduly narrow. A more plausible conception

of harm, according to those theorists, accepts that the choice to bring a less well-off

person into existence may be considered to harm – or at least to wrong, or to be bad

for – that person because it brings a person into existence whose well-being level

falls below a “decent minimum” (Steinbock 2009), or because it causes that person

to suffer substantial pain or impairment (Harman 2004, 2009), or because “restricted

lives” can be “intrinsically undesirable” (Kavka 1981: 105).

A related proposal brings the concept of a right to bear in analyzing nonidentity

cases. On that view, future people have a right to have a certain kind of life, and when

we bring people into existence who cannot enjoy that kind of life, we violate that right

even in the case where their very existence depends on the right being violated (Persson

2009; Velleman 2008: 277; Reiman 2007: 78–86, 92; Woodward 1986: 811–26).

Still another proposal is premised on the idea that different types of nonidentity

problems are subject to different analyses. Hanser thus argues that in some cases, but

not others, the choice under scrutiny is related to the undesirable condition in a way

that makes it appropriate to say that the agent is responsible for that condition. Parfit’s

risky policy case would fall, according to Hanser, into the first category, while the

choice to bring a genetically impaired child into existence would fall into the second

(Hanser 2009: 184–95).

The approach Roberts suggests also divides the cases. One horn of that approach

objects to the “no harm done” result that the nonidentity argument tries to establish

in cases such as depletion. The basis for the objection is that it is a fallacy to think

that what we intuitively consider the morally lesser choice somehow makes it any

more likely that a particular person will eventually exist than any seemingly better

choice does. In other words, Harry’s existence is highly precarious under the choice

of conservation, but it is just as highly precarious under the choice of depletion. The

other horn of that approach accepts that still other types of nonidentity problems –

e.g., genetic impairment cases – do compel us to accept the “no harm done” result.

However, Roberts, like Heyd, argues that, for those cases, it remains unclear that the

choice under scrutiny is wrong (2009a: 209–10; 2007).

Still another approach has been to contest the view that the lives at issue are truly

worth living. If never existing is the preferable state, then the view that causing a

person to exist generally harms that person can be pressed (Benatar 2006; Ryberg

2004).

Finally, many theorists consider the various challenges of population ethics to

show that a more agent-oriented, intention-based perspective is in order (Wasserman

2009: 265–85; Kavka 1981). Consequences remain important but do not on their

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own lead to a full understanding of how the choice to bring a person into a burdened

existence is to be evaluated.

See also: climate change; cloning; consequentialism; population; reproductive

technology; repugnant conclusion

REFERENCES

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Boonin, David 2008. “How to Solve the Non-Identity Problem,” Public Affairs Quarterly,

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Hanser, Matthew 2009. “Harming and Procreating,” in Melinda A. Roberts and David

T. Wasserman (eds.), Harming Future Persons: Ethics, Genetics and the Nonidentity

Problem, Dordrecht: Springer, pp. 179–200.

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Heyd, David 2009. “The Intractability of the Nonidentity Problem,” in Melinda A. Roberts

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Nonidentity Problem. Dordrecht: Springer, pp. 3–25.

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vol. 11, pp. 93–112.

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University Press.

McMahan, Jeff 2009. “Asymmetries in the Morality of Causing People to Exist,” in Melinda

A. Roberts and David T. Wasserman (eds.), Harming Future Persons: Ethics, Genetics

and the Nonidentity Problem. Dordrecht: Springer, pp. 49–68.

Narveson, Jan 1976. “Moral Problems of Population,” in Michael D. Bayles (ed.), Ethics and

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Position,” Philosophy and Public Affairs, vol. 35, pp. 71–92.

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T. Wasserman (eds.), Harming Future Persons: Ethics, Genetics and the Non-Identity


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Choice to Harm to Persons,” Law and Philosophy, vol. 28, pp. 1–57.

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Tännsjö, Torbjörn 2004. “Why We Ought to Accept the Repugnant Conclusion,” in Jesper

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Ethics. Dordrecht: Kluwer, pp. 219–37.

Temkin, Larry 1993. Inequality. New York: Oxford University Press.

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Velleman, David 2008. “Persons in Prospect,” Philosophy and Public Affairs, vol. 36, pp. 221–322.

Wasserman, David T. 2009. “Harms to Future People and Procreative Intentions,” in Melinda



Woodward, James 1986. “The Non-Identity Problem,” Ethics, vol. 96, pp. 804–31.

FURTHER READINGS

Cohen, Cynthia 1996. “‘Give Me Children or I Shall Die!’ New Reproductive Technologies

and Harm to Children,” Hastings Center Report, vol. 26, pp. 19–27.

Holtug, Nils 2010. Persons, Interests, and Justice. Oxford: Oxford University Press.

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Kumar, Rahul 2003. “Who Can Be Wronged?” Philosophy and Public Affairs, vol. 31,

pp. 99–118.

Rivera-Lopez, Eduardo 2009. “Individual Procreative Responsibility and the Non-Identity

Problem,” Pacific Philosophical Quarterly, vol. 90, pp. 336–63.

Robertson, John 1994. Children of Choice: Freedom and the New Reproductive Technologies.

Princeton: Princeton University Press.

Sher, George 2005. “Transgenerational Compensation,” Philosophy and Affairs, vol. 33,

pp. 185–200.

Shiffrin, Seana 1999. “Wrongful Life, Procreative Responsibility, and the Significance of

Harm,” Legal Theory, vol. 5, pp. 117–48.

Shiffrin, Seana 2009. “Reparations for U.S. Slavery and Justice Over Time,” in Melinda



Weinberg, Rivka 2008. “Identifying and Dissolving the Non-Identity Problem,” Philosophical

Studies, vol. 137, pp. 3–18.

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