Surveys
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
www.surv-perspect-integr-environ-soc.net/1/39/2008/
© Author(s) 2008. This work is distributed under
the Creative Commons Attribution 3.0 License.
Theories of intergenerational justice: a synopsis
A. Gosseries
Permanent Research Fellow, Fund for Scientific Research (FRS-FNRS),
Chaire Hoover d’éthique économique et sociale,
3, Place Montesquieu – 1348 Louvain-la-Neuve, Belgium
Received: 7 March 2008 – Revised: / – Accepted: 20 April 2008 – Published: 15 May 2008
Abstract. In this paper, the author offers a synoptic view of different theories of intergenerational justice,
along two dimensions (savings/dissavings) and three modalities (prohibition, authorisation, obligation). After
presenting successively the indirect reciprocity, the mutual advantage, the utilitarian and the Lockean approaches, special attention is given to the egalitarian theory of intergenerational justice. Two key differences
between the egalitarian view on intergenerational justice and the sufficientarian interpretation of sustainability
are highlighted.
Keywords. generations, sustainable development, just savings, indirect reciprocity, lockean proviso, Brundtland, Rawls, justice
“(. . . ) comme si l’homme n’était jamais seul, comme s’il
avait reçu en partage une matière et une force, offrande qu’il
devait à son tour transmettre par l’entremise d’un être ou
d’un acte . . . ” (Márai, 1993:164)1
1
Introduction
We have been facing threats to our environment and the risk
of depletion of natural resources for a very long time. To such
an extent, that they even appear to be determining factors in
the decline of certain civilisations. One of the explanations
given for the collapse of the Easter Island civilisation is resources overexploitation (See e.g. Ponting, 1993; Diamond,
2005). Lead poisoning, which is very ancient, is said to
have contributed to the fall of Rome (Gilfillan, 1965; Lessler,
1988; Bränvall et al., 2001). Despite technological progress,
we remain highly dependent on our environment as well as
on natural resources. The scale and the nature of these issues
have admittedly evolved over time. Yet, our philosophical
theories on justice fall astonishingly short of expectations in
attempting to deal with the normative issues raised by environmental and resource depletion problems. Emphasis on
Correspondence to: A. P. Gosseries
(axel.gosseries@uclouvain.be)
1
“as though man were never alone, as though he had inherited substance and strength, a gift which he must in turn hand on,
through a being or an action’’.
the long term, the concept of pollution and the issue of externalities are potent challenges to our attempts at articulating
equitable rules for individual behaviour and social organisation. Simultaneously, new concepts are constantly emerging
from political and scientific debate, such as “sustainable development”, “ecological debt”, “degrowth” and “ecological
footprint” (See e.g. Maréchal and Quenault, 2005 on the former). They represent as many invitations to revisit de novo
the nature of normative issues at stake. In order to do that,
these emerging concepts must be retranslated every time into
the specific language of each theory of justice. Otherwise,
it would be impossible to link environmental and natural resources issues with all the other societal challenges we simultaneously have to cope with in today’s world.
The concept of sustainable development is extraordinarily fashionable. There is no doubt that a requirement for
intergenerational justice constitutes one of its key components. In fact, its most popular definition is development that
“Meets the needs of the present without compromising the
ability of future generations to meet their own needs (WCED,
1987:53). Yet, despite the degree of sophistication in evidence elsewhere in theories of justice, discussions on sustainability devote too little attention to a thorough examination of
what intergenerational justice might actually mean. We must,
however, underline that several other normative dimensions
should also be considered so as to deal exhaustively with environmental matters. Firstly, issues of international or interspecific equity are crucial also. But local justice (in the geographical sense) or gender issues cannot be neglected either.
Published by Copernicus Publications on behalf of the Institut Veolia Environnement.
40
A. Gosseries: Theories of intergenerational justice: a synopsis
For some of the environmental challenges, these dimensions
are even more significant in practice or conceptually more
challenging than the intergenerational dimension in isolation.
Furthermore, as we are focusing on the notion of sustainability, it is essential to differentiate two issues: “Should “it”
endure, and if so, why?” and “Since it probably will endure,
how should we go about making sure to do so equitably?”.
We can reply to the latter question while sticking to an agnostic stance on the former question. This in no way means
that we are denying the importance of considering the very
possibility that we might all decide to cease having children,
and to think about its meaning. This hypothetical situation
raises several issues. For example, the very fact that human
reproduction would then cease implies the end – a voluntary
end in this case – of the human species. Would the actions
leading to such an outcome have to be considered immoral?
Hans Jonas’ thoughts are often referred to as being central,
although we are not in fact inclined to consider that his characterisation of the alleged immorality at stake here is entirely
plausible (Gosseries, 2004a:18–22). Furthermore, the hypothetical case of generalised refusal to have children also puts
us in the situation of a “last man” which invites reflection on
the moral status of non-human animals (see e.g. Gosseries,
1998:401–405).
We should therefore remain aware of the specific niche of
the intergenerational dimension so that we do not attempt to
force into the subject problems which would best be analysed
from other angles. Furthermore, if we focus on the intergeneration issue, it is essential to compare the treatment proposed for environmental problems with what would be proposed for other matters which are just as important for intergenerational equity, such as public debt management, funding of pension schemes or passing on a language. This paper
aims to demonstrate that justice between generations can be
understood in different ways and that some are more robust
than others. It also aims to explain why sustainable development as defined in the Brundtland report (WCED, 1987)
is unable to exclude two major kinds of intergenerational injustice that we propose to highlight. It is up to readers to
consider whether the intuitions relating to justice that they
would endorse in the intergenerational context are consistent
with the intuitions to which they would be committed with
respect to similar problems in a strictly intragenerational setting.
2
Tool box
In view of the scale of environmental issues, it could be very
tempting to postulate at the outset that unprecedented conceptual challenges should be associated to them, requiring a
complete revision of our general theories on justice. We cannot exclude that this might well be the case. However, we
intend to work from the opposite assumption and to begin by
using as best we can available conceptual resources before
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
exploring whether anything remains unaccounted for, requiring the use of a radically new approach. To use an analogy,
before coining new words or inventing a new language, let
us see whether an existing language – in this case theories of
justice – painstakingly constructed by successive generations
of practitioners does not already provide sufficient vocabulary to deal with the issues in hand.
There are different ways in which a layman can be introduced in a reasonably intuitive fashion to intergenerational
equity issues. One of them is to refer to rules for the use of
common spaces by successive users. Consider the metaphor
of the uninhabited mountain hut. We can take a certain number of rules commonly found posted in this kind of refuge
and use them as points of departure for general theories. The
following could be compared: “Please leave the premises
clean”, “. . . as clean as you would have liked to find them on
arrival” or “. . . as clean as they were when you arrived”. All
of these are starting points for theories of intergenerational
equity based on different logics and with a different content.
Another possible point of entry consists in envisaging the
nature of our intergenerational obligations through the prism
of concepts of private law, focusing specifically on the idea
of property as well as on specific types of contracts. Consider the famous native American saying: “Treat the Earth
well: it was not given to you by your parents, it was loaned
to you by your children. We do not inherit the Earth from
our Ancestors, we borrow it from our children”. It refers to
a loan contract, the next generation being the lender and the
current one the borrower. This is not the only existing proposal. Burke (1909–14:§165) refers in general terms to the
idea of a partnership “Between those who are living, those
who are dead, and those who are to be born”. The Pennsylvanian constitution (art. 1, §27) uses the idea of common
property. Locke (1690 (2003): First Treatise, §88) refers to
an idea of joint possession at the overlap. The Japanese constitution (art. 97) uses the notion of an intergenerational trust.
Jefferson (1789) claims that “The earth belongs in usufruct to
the living”. And Jaurès (1902) even worked out a concept of
“everlasting mortgage”. We should not exclude that lessons
may be learned from a closer look at the potential and limitations of each of these proposals. Note that once such a full
conceptual clarification has been made, it will be useful to
re-translate such findings in the specific language of general
theories of justice.
Using the mountain hut metaphor or referring to various
kinds of contracts or types of rights in rem are helpful forms
of introduction to the subject. Yet, they are only partially illuminating. The approach we intend to use here will be constructed a little differently. It will compare different philosophical theories of justice along two lines. Firstly, only
the size of the basket to be passed on to the next generation will be of concern, not its composition. This basket is
filled with the components which make up a capital, in the
broadest sense of the word. Such capital is not only physical,
but also technological, institutional, environmental, cultural,
www.surv-perspect-integr-environ-soc.net/1/39/2008/
A. Gosseries: Theories of intergenerational justice: a synopsis
relational, etc. We will therefore propose a table to summarise the key-conclusions of each of these theories, based
on two concepts: generational savings and dissavings. Savings occur (generationally speaking) when one generation
transfers to the next a capital (in the extended meaning of
the word) which is greater than the one it inherited from the
previous generation. Inversely, there are generational dissavings whenever one generation transfers to the next a capital
which is smaller than the one it inherited. We will then go
on linking these two concepts (savings/dissavings) to three
modalities: authorisation, prohibition and obligation.
This approach may seem both desperately simplistic and
excessively quantitative. And yet, the use of the savings/dissavings concepts – on top of the fact that they refer to
a very broad understanding of the word “capital” – first of all
seek to highlight how much the various theories of justice, as
applied to the intergenerational realm, differ from each other
both in terms of rationale and of practical implications. Furthermore, we certainly do not deny the importance – and the
possibility – of a debating on the contents of the basket to
be passed on from one generation to the next. This would
require more than just weighing the significance of environmental assets and comparing them with other requirements,
such as those connected to the transmission of special cultures or the preservation of mechanisms of solidarity. Even
among the environmental questions themselves, selections
are also to be made between, for example, dams generating
green energy and endangered species, between preserving areas in their natural condition and human intervention to save
certain species that are to be found there, etc. (see Gosseries,
1997).
Finally, two further points should be noted. On the one
hand, since the present paper is intended to provide a synopsis, we will not be proceeding with a detailed examination
of more applied issues where intergenerational justice matters, such as defining the level of a global cap on CO2 emissions, justifying the preservation of biodiversity, or selecting
a funding scheme for the dismantling of our nuclear power
stations (see respectively: Gosseries, 2006b, 2004a:241–265,
2008). On the other hand, intergenerational justice also raises
the issue of our obligations to past generations. This dimension, which we are also not intending to broach in this paper,
is present at several levels, including in some the theories
presented below. It is also particularly relevant for specific
environmental issues, such as the integration of past CO2
emissions in the definition of the current share of obligations
to reduce emissions (see Gosseries, 2004b). That being said,
let us now consider the crux of the matter.
3
Indirect reciprocity
One theory, discussed in particular by Brian Barry (1989),
is the indirect reciprocity theory (see de Shalit, 1995:96–99;
Gosseries, 2006a). The general idea of reciprocity presupwww.surv-perspect-integr-environ-soc.net/1/39/2008/
41
poses that in the event people are able to do so, they are under
an obligation to return to others what they themselves have
received from them. In the case of intergenerational justice,
one can assume that the idea of reciprocity is sociologically
widely endorsed in the public (see Wade-Benzoni, 2002). In
its “descending reciprocity” version, it breaks down into two
maxims. The first one seeks to explain why we are obligated
to the next generation. In this case, it is because we received
something from our parents that we must transmit something
“in return” to our children’s generation. The intuitive idea
can then be accounted for in certain ways in the language
of property or more directly as reciprocation for an effort
on the part of our parents. But this differs for example
from the idea that if we owe our children anything, it is
because in fact we are only borrowing what already belongs
to them. It also differs from egalitarian logic as we shall
see. Regarding the second maxim, it defines the content
of our obligations to the next generation. As a result, we find:
Descending reciprocity
– Justificatory maxim: The current generation owes
something to the next generation because it received
something from the previous one.
– Substantive maxim: The current generation must pass
on to the next a capital at least equivalent to the one it
inherited from the previous one.
For those who associate justice with reciprocity, indirect
reciprocity is quite a potent idea. It has the advantage of justifying obligations to people who so far have never given us
anything and who may be giving us less in the future than
what we will have given them. In the case of direct reciprocity, it is the original benefactor who ends up getting back
what he put in, whereas with indirect reciprocity, there is a
third party who benefits (in this case: the next generation)
instead of the initial benefactor (in this case: the previous
generation), giving rise in this way to a chain of obligations.
An obvious objection could be that a simple donation cannot
in itself justify a return obligation. However, the nature of
the moral difficulty arising out of non-reciprocation in this
case can be accounted for through reference to the idea of
a free-rider, getting a free ride on the intergenerational railway without buying his ticket, and therefore taking advantage without any counterpart of the sacrifices made by all the
preceding generations.
What are the obstacles in the way of the indirect descending reciprocity view? Firstly, if we refuse to dissociate the
existence of an obligation to the initial benefactor and that
of an obligation to the third party beneficiary, the justificatory maxim presupposes the idea that we have obligations
to past generations, i.e. to the dead. It is in fact those obligations which are the source of our obligations to the next
generation. However, for a state to justify its sustainable development policies by reason of obligations to the dead is a
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
42
challenge to the liberal requirement of neutrality on the part
of the state towards various metaphysical conceptions and
views of the good life. It can be demonstrated that such obligations to the dead only make sense if it is postulated that
the dead do exist in a sense that is morally relevant. Yet, we
do not all subscribe to this postulate, which makes it difficult
to see it as metaphysically unproblematic (Gosseries, 2004a:
chap. 2).
Moreover, the justificatory maxim fails to justify the first
– be it hypothetical – generation’s intergenerational obligations, because by definition such a first generation did not
receive anything from a previous generation. How could
we then explain what the problem would if a first generation were to squander from the outset a considerable part of
the capital available to it? For that matter, were we to view
each generation as a first generation insofar as the goods it
invented or discovered are concerned, it would become immediately apparent that the present difficulty is necessarily
devoid of practical implications.
A few other points could be mentioned – such as the difficulties encountered by the substantive maxim in case of demographic fluctuations. It should also be underlined that descending indirect reciprocity is not the only possible form of
the idea of reciprocity in the intergenerational realm. For the
sake of comprehensiveness, let us also point at the ascending
indirect reciprocity idea (relevant for example to explain the
logic of pay-as-you-go retirement schemes) as well as at the
double reciprocity concept (Cosandey, 2003) which involves
direct reciprocity transfers between generations. However,
these two alternative forms of intergenerational reciprocity
are not directly relevant to the environmental field which constitutes our focus point here (Gosseries, 2006a).
In any event what really matters in this context, is to emphasise the need to check whether indirect reciprocity really
reflects our intuitions about justice, both intergenerationally
and as a component of a general theory of justice. The simplest method for such a purpose consists in testing the idea of
reciprocity in an intragenerational context. Take for example
the case of a person with multiple congenital disabilities. Let
us accept the idea that she will give us less in return for what
we as a society gave to her – which is not meant to deny the
benefits we may of course derive from her company. Given
such an example, the limitations of the idea of reciprocity
are clear. As regards justification, is it because that person
(or someone else) gave (or will give) us something that we
feel obliged to care for this dependent person – as a matter
of justice? The reply is probably negative for many of us.
And on the substantive side, should I measure the dimension
of what I owe this disabled person on the basis of what he
or she gives me in return? Here again, the answer will be
in the negative for many of us. This suggests that for many
of us, over and beyond internal consistency difficulties, the
idea of reciprocity is not fully capable of reflecting intuitions
of justice in general and in the intergenerational context in
particular.
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
A. Gosseries: Theories of intergenerational justice: a synopsis
4
Mutual advantage
The idea of mutual advantage is not very distant from that of
reciprocity. Yet, it is not identical, both in logic (what justifies the existence of obligations) and by its demands (for
instance, the idea of guaranteeing the promised transfers between actors in a cooperative game). Briefly, a theory of
justice based on the idea of mutual advantage has to show
that a “rational” agent – i.e. one acting exclusively out of
self-interest – will serve his best interest by engaging in a
cooperative venture and submitting to certain social rules accordingly. The point therefore is to demonstrate that it is rational – in a narrow sense – to be fair and that rules of justice
must be justified by reason of rationality – in this same narrow sense. In practice, this requires the demonstration that
gains may result from cooperation between individuals and
that these gains can make every one of us net beneficiaries of
such cooperation.
In an intergenerational context, we therefore need to check
how the idea of cooperation can be transposed. A key difficulty in this respect is related to the issue of intergenerational
overlap (Gauthier, 1986: chap. IX–6). The fact that not all
generations are – not even temporarily – contemporary is a
challenge on two counts. Firstly, does this not threaten the
very possibility of the benefits of cooperation being mutual?
Because if benefits are real but are only in favour of certain
generations, so that others are net contributors, a theory of
mutual advantage would be incapable of justifying that all
generations should submit to a common rule of justice. Replying to this question amounts to asking to what extent the
possibility of descending benefits (from one generation to the
next) and ascending benefits (from one generation to the previous one) depends on these generations overlapping with
one another. Furthermore, not only must it be possible for
benefits to be mutual, but there must also be a guarantee that
the conditions exist for the rule of cooperation to be effectively respected by each generation. In this case again, the
non-contemporary nature of many generations in respect of
each other challenges the possibility of enforcing respect of a
given rule of intergenerational transfer. The degree to which
a threat of ascending or descending sanctions can remain
credible in the absence of intergenerational overlap therefore
remains to be ascertained.
This twofold challenge is compounded by a further question: supposing it is possible to construct an intergenerational
model in such a way as to successfully address this challenge,
there will still be a need to verify what that implies in relation to our question on savings and dissavings. It would
be perfectly possible to imagine that it is rational for each
generation to submit to a rule, which would nevertheless be
compatible with a gradual deterioration of the stock of resources transferred by each generation to the next. There
is an ongoing debate on this point (Heath, 1997; Arrhenius,
1999), but it has not reached a point where clear conclusions
can be drawn (see Gauthier, 1986:302–305). It is however
www.surv-perspect-integr-environ-soc.net/1/39/2008/
A. Gosseries: Theories of intergenerational justice: a synopsis
obvious that any serious attempt at articulating a theory of
justice from the angle of mutual advantage cannot elude an
in-depth examination of such difficulties.
5
Utilitarianism
Let us now explore a very different theory: utilitarianism. It
is characterised not only by its preoccupation with people’s
welfare (utilitas in Latin) but more particularly with the idea
that a fair organisation of society is one which maximises
the aggregate welfare of its members (See e.g. Smart and
Williams, 1973). This is why we can refer to it as an aggregative theory. There are several unsound reasons for criticising utilitarianism. Yet, it is entirely true that this theory
of justice is not primarily concerned with the distribution of
welfare among the members of society. What matters is the
size of the welfare pie from which society as a whole will
benefit, not the relative size of the pieces of that pie each
member will be receiving. Hence, sacrificing entirely the
well-being of a few people (to the point for example where
they are reduced to slavery) making it possible to maximise
society’s well-being as a whole (by the fact that a large portion of society would benefit from the slavery imposed on a
tiny minority), could be the policy advocated by utilitarians
in specific circumstances. Therefore, more than any other
theory of justice, this one is likely to lead to sacrificial consequences, although in its more elaborate versions, it does try
as best it can to avoid such counterintuitive outcomes.
In an intergenerational context, there is one fact that plays
a crucial role in this respect. Giving up the consumption
of part of our capital today may enable us – provided it is
wisely invested – to consume much more of that capital at
some more or less distant future time. Consider a bag of
seeds, part of which could be either consumed immediately
or sown so as to multiply its volume. If you are a utilitarian, savings (in generational terms) are not just authorised;
they are required since the goal is to maximise the size of the
intergenerational welfare pie. This means that the first generations in history have to tighten their belts and invest for the
benefit of future generations. A point worthy of mention is
that the idea of productive investment, which is central to this
theory, is not necessarily linked to the number of generations
following us – at least for investments whose return does not
depend solely on human activity, but rather to the fact that
they will be arriving after us.
This result leading, in a way, to sacrificing the earlier generations is magnified by two extra – and independent – factors. On the one hand, it is realistic to postulate some intergenerational altruism due partly to the fact that the succession of generations is also linked to biological parent-to-child
relations which inevitably generate a certain degree of altruism. It is also plausible to postulate that this altruism is asymmetric, being stronger from parent to child than from child to
parent. If such a descending altruism is taken into account,
www.surv-perspect-integr-environ-soc.net/1/39/2008/
43
an extra degree – and in this case a purely voluntary one –
of saving may be added to the obligation to save referred to
above. In other words, descending altruism could further intensify the generational savings trend already present in the
utilitarian model. Nevertheless, it does not necessarily lead
to an additional welfare differential if the actors themselves
derive well-being from these altruistic acts. On the other
hand, the utilitarian conclusion becomes more worrying if
it is accepted that the number of coming generations is, if not
infinite, at least indefinite. For one way of interpreting utilitarianism consists in forcing us into everlasting sacrifices,
since there is no way of knowing where they should stop.
Such a sacrifice would ultimately be to no one’s benefit, since
every generation would be obliged to save given the permanent uncertainty as to how many generations would follow.
Utilitarians are well aware of this problem. Let us therefore emphasise two factors pointing in the opposite direction. Firstly, a factor which could attenuate the scope of the
obligation to save is diminishing marginal utility, a (fairly
plausible) postulate traditionally referred to as a justification
for aggregativists’ concern for the distribution of levels of
well-being (see Gauthier, 1986:305). The underlying idea
is that the more a person has of a given good (e.g. apples),
the less an additional good will bring her additional utility.
This means that if we have an extra apple, it should be given
to the one who has less apples if we aim at maximizing the
additional welfare generated by this apple. But more importantly, there is another idea, the one of a social discount rate.
This has been the subject of extensive philosophical debate
for decades (see e.g. Cowen and Parfit, 1992; Birnbacher,
2003). And one recent instance is to be found in the discussions surrounding the Stern report on the economics of
climate change (Stern, 2007). The idea is simple: if the rate
is positive, a unit of future welfare will be granted less value
than the same welfare unit produced today. A discount rate
of this kind can meet certain concerns besides addressing the
single “sacrificial” issue mentioned above. For example, it
would be possible to give a lower discounted value to a future welfare unit because of the uncertainty as to its actual
future existence. However, when it is simply a question of
a pure time preference for the present, it becomes morally
problematic once applied to relations between different individuals (rather than to merely planning the welfare profile
within one’s own existence). In fact, the idea can be put
forward that at that level it is still only an attempt - an ad
hoc (Rawls, 1999:262) and rather ineffective one – to reduce
the size of a problem – i.e. an inclination toward sacrificing
earlier generations – which is in fact the logical outcome of
utilitarianism.
Even if descending altruism is left aside, the conjunction
of recognising the productive nature of capital (whenever
properly invested) and the indefinite nature of the number
of future generations is such that, in the intergenerational
context, utilitarianism can lead to particularly sacrificial outcomes, albeit attenuated by the inclusion of diminishing
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
44
A. Gosseries: Theories of intergenerational justice: a synopsis
marginal utility as well as the introduction of a social discount rate. The reason why such outcomes seem especially
unacceptable to many of us probably has to do with the fact
that our conception of justice generally involves a distributive motive besides or instead of an aggregative one.
6
Lockean proviso
Before examining the paradigmatic example of a distributive
theory of justice – Rawlsian egalitarianism – let us consider
yet another family of theories. This time, it is neo-Lockean
rather than neo-Hobbesian, and is commonly referred to as
libertarianism. Briefly, libertarian views are building on two
core features: On the one hand, a definition and a strong
protection of self-ownership; on the other, a particular way
of broaching the subject of ownership of external resources
– in contrast to internal resources which are part of selfownership. In this way, libertarians aim at guaranteeing, both
against state and third party intervention, a strong protection
for people’s physical integrity as well as e.g. for the ownership of their talents. What is of particular interest here,
however, is the status of external resources. We need in this
respect to determine how to allocate to members of society
the property of the goods we have inherited.
Consider a first generation allocating the property of arable
land. Some libertarians would incline to allocate ownership
of such property on the basis of a rule of the “first come,
first served” variety, which for that matter is a rule in use in
various sectors of society, for instance as regards intellectual
property rights. Others would have us subordinate legitimacy
of appropriation to complying with so-called “Lockean” provisos. In general, the difference between those two major
approaches will reflect, coexist with or result in differences
in perceptions of the initial patrimonial status of external resources. For some, generally right-wing people, arable land
initially does not belong to anyone, hence the use of the first
come, first served principle. For others, generally more leftwing, the initial status of external resources would be that
of collective property, which would explain the need for respecting a Lockean proviso. One difficulty is that the idea
of a Lockean proviso is interpreted in different ways, depending on whether Nozick’s views or those of others are
adopted (Vallentyne and Steiner, 2000). What did Locke really mean when he said that initial appropriation can be legitimate “At least where there is enough and as good left for
others” (Locke, 1690: second treatise, §27; Waldron, 1979)?
Let us be more direct in our formulation: “At least where
there is as much which is left in common for others”. Applied to the intergenerational domain, this could give us for
example Arneson’s formulation: “The continued legitimacy
of private ownership from the standpoint of self-ownership
depends on each successive generation obtaining the equivalent of a per capita share of unimproved, undegraded land”
(Arneson, 1991:53).
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
A libertarian theory wishing to apply such a Lockean proviso will first of all need to determine its content (“as much as
what?”) and apply it specifically to the intergenerational context (see Elliot, 1986:217ff.; Arneson, 1991:52–53; Steiner,
1994:268–273; Wolf, 1995:791ff.). Let us outline three versions applicable to the intergenerational domain. A first possible interpretation is: each generation should leave to the
next at least as much (or the equivalent) of what the first
(prehistoric) generation initially appropriated for itself. For
those who consider that the basket of goods inherited from
the immediately previous generation exceeds far and away
the value of what the prehistoric generation would have had
access to, this formulation of the proviso may appear too lax.
For it would authorise the entire generation to dissave, inasmuch as the resources transmitted in fine to the next generation are in no way less substantial, as regards their productive
potential, than the resources available to the (first) prehistoric
generation. In effect, that formulation could be amended in
two ways.
The first consists in taking into account the natural modifications of our resources as time goes by. Let us imagine
that the generation before us was the first to be victim of a
minor ice age which will continue for two generations. Ex
hypothesi, this overall has a negative impact (as regards land
productivity, biodiversity, etc.). Should the present generation compensate for the difference – originating in natural
events – between the value of the prehistoric world and what
it has in effect become due to natural circumstances? For a
Lockean, there is no particular reason why this should be so.
What matters as a reference scenario to implement such a
Lockean proviso, is to be able to identify what other people’s
situation would have been in my absence – in this case, the
situation of any previous generation if it had been the first.
The following alternative formulation therefore seems commendable: each generation must leave to the next at least as
much as what the next generation could have appropriated in
the absence of any previous generation, or preferably2 , what
the coming generation would otherwise have inherited if no
previous generation had by its actions brought about a net
improvement or a net deterioration.
Let us however imagine a hypothetical situation where
some of the previous generations – and not this time natural
disasters – had damaged, without any compensating technological improvements, the state of external resources compared to what they would have been if left to the sole effect
of natural causes. Using the above proviso, there would be
an obligation to save. Now why should the current generation bear the cost of compensating for deteriorations brought
about by the activity of previous generations and for which
they are in no way responsible, or at least no more so than the
coming generation in whose favour it seeks to meet its obligations? Conversely, for those who consider that the cultural
capital inherited from our ancestors considerably increases
2
I owe this improved formulation to P. Vallentyne.
www.surv-perspect-integr-environ-soc.net/1/39/2008/
A. Gosseries: Theories of intergenerational justice: a synopsis
the productive potential of natural resources which the next
generation would have inherited in the absence of any previous generation, the degree to which such a formulation
authorises anew a very significant margin of dissavings becomes apparent.
A further reformulation of the Lockean proviso is however
possible: each generation must leave to the next at least as
much as what the next generation could have appropriated if
the current generation had not contributed by its action to a
net improvement or deterioration of what the following generation would otherwise have inherited. This third interpretation takes into account not just the natural improvements
or deteriorations that have occurred since prehistoric times.
It also includes the accumulated product of the physical and
intellectual activities of the generations which preceded the
current one. The only thing we need to do then is to consider what would have been the situation of each generation
in terms of external resources (both natural and cultural), not
in the absence of all previous generations, but rather in the
absence of the single preceding generation.
In the language of savings and dissavings, that means that
savings are authorised, whereas such a Lockean proviso in
no way authorises dissavings, unless the environment which
the next generation will inherit has deteriorated compared
to what we ourselves inherited, for reasons unrelated to our
own activity (i.e. natural events or resulting from the activity of previous generations). This implies, for example, that
any climate change resulting from strictly historical emissions (i.e. resulting from our ancestors’ activities only, not
from ours) and which would lead to a worse climate for the
next generation than for our own, would not imply for us any
specific obligations – which by the way shows that the question of historical emissions raises not just transgenerational
equity issues (Gosseries, 2004b), but also issues relating to
intergenerational equity. While what would be defended in
this case by a proponent of indirect reciprocity is not entirely
clear, the egalitarian view would clearly differ here from the
Lockean one. Be that as it may, we are concentrating here
on possible differences between “at least as much as what
prehistoric generations had”, “at least as much as what G+1
would have had in the absence of any earlier generations”
and “at least as much as G+1 would have inherited in the
absence of G only”. And the specificity of the Lockean approach is to focus on the question of knowing to what extent
my existence deprives someone else of something he could
otherwise have benefited from.
7
Rawlsian egalitarianism
Rawls, in his masterpiece “A theory of Justice” (1999:§44),
is aware of utilitarianism’s major difficulties in the intergenerational context. At the same time, he considers that moving
away, be it minimally, from the initial condition of prehistoric men is necessary, not just for reasons of efficiency, but
even for reasons of justice. How can both these concerns be
www.surv-perspect-integr-environ-soc.net/1/39/2008/
45
accommodated? By defending a “two-stage” model in which
a steady state phase follows an accumulation phase. During
the accumulation phase, principles are identical to those of
utilitarianism (compulsory savings). But this phase is supposed to have a limited duration. And the rationale underlying the need for such accumulation is totally unrelated with
maximising the size of the intergenerational welfare pie. For
Rawls, the aim of the accumulation phase is to allow economic affluence to build up so that at least minimal stability to just institutions can be ensured. As soon as this point
is reached, accumulation ceases to be an obligation and the
steady state phase begins. And for that second phase, the
principle defended by Rawls is identical to the one defended
by the indirect reciprocity view.
Like Rawls, we believe that such a “two-stage” approach
is necessary. We also believe that he is justified in defending
the principle of an obligation to save during the accumulation
phase (for a full discussion: Gaspart and Gosseries, 2007).
However, this second thesis is not self-evident. What is potentially shocking for an egalitarian like Rawls, is to propose
for the accumulation phase a principle of compulsory savings
that goes against a concern for the worst off. In fact, from this
viewpoint it is unfair, strictly speaking, to demand savings
from the first generations. Doing so would bring about an intergenerational world where the least well off are not as well
off as they could possibly be. Merely sticking to a prohibition on dissavings would not have such consequences. Rawls
is aware of this problem but still insists on an obligation to
save. Let us attempt a brief defence of Rawls’ position the
principle applicable to the accumulation phase.
His theory is not just egalitarian, it is also liberal but in
a very specific sense which must not be confused with its
usual meaning in the designation of certain political actors
on the European political arena. It is liberal in the sense that
pursuing the improvement of the situation of the least well
off must be done within the constraints we refer to as “basic
liberties”. In other words, defending those few basic liberties (physical integrity, freedom of speech, etc.) takes priority over the objective of improving the social and economic
condition of the underprivileged. It could then be said that
the reason why a violation of the egalitarian objective is allowable in the accumulation phase, has to do with the aim
of setting up as quickly as possible institutions which could
then be able to defend personal basic liberties and that this
latter objective takes priority over the former. Now, if we can
demonstrate that the richer (in terms of GDP) a democratic
State becomes, the more likely are its chances of retaining its
democratic character, we are in possession of an empirical
argument able to support the claim that setting up equitable
institutions requires a certain level of affluence. Although we
can agree with the “two-stage” theory and with the principle
Rawls defends for the accumulation phase, we believe that
an upholder of equality of opportunity should be defending a
different principle in the steady state phase. And what principle should that be?
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
46
8
A. Gosseries: Theories of intergenerational justice: a synopsis
Egalitarianism revisited
We do not believe that Rawls is entirely true to the demands
of egalitarianism in the steady state phase. We consider that
prohibiting dissavings should go hand in hand with prohibiting savings. This may sound absurd. Is it at all unfair for parents to voluntarily scrimp and save to provide a better life for
their children than the one they could have had themselves?
Who could the victims of such allegedly unjust behaviour
be? The answer to this question is that the victims would
be the least well off members of the generation of such parents. Let us consider the situation of a generation anticipating that, at the end of its existence, it might have transferred
a surplus to the next generation in comparison with what it
had received from the previous generation. The theory we
are defending here is that it should not be the next generation
taken as a group that should be benefiting from this surplus,
but rather the least well off members of the current generation. To transfer a surplus into the future sacrifices to the
same extent today’s least well off. It is only if each generation adheres to the principle of prohibiting both savings and
dissavings that the intergenerational world that we will build
can be seen as one where the least well off, regardless of the
generation to which they belong, will be better off than they
would have been in any other alternatively organised world.
Note that this prohibition on savings has nothing to do with
a preference for the members of our own generation. It is
derived from a generational impartial concern for improving
the situation of the least well off, whichever generation they
belong to. Admittedly if this surplus were passed on to the
next generation, it could well benefit the least well off members of that generation. But what we would have to make
sure of is that the least well off members of our own generation would not end up then in a worse situation than the one
experienced by the least privileged of the next generation.
We cannot go into the details here of this rather counterintuitive principle, or which at least seems to be so at
first sight (for a more extensive defence: Gosseries, 2004a:
chap. 4; Gaspart and Gosseries, 2007). But we must emphasise that even if such an approach is not totally incompatible
with the idea of growth, it should certainly be contrasted with
other ideas in the “anti-growth” family of arguments (see
Gosseries, 2004a:224–225, Gaspart and Gosseries, 2007).
Among these, let us mention four, all different from the one
defended here. The first consists in stating that growth, in
so far as it would lead to increased inequalities internationally, would be unfair in this respect. The second underlines
that the adoption by a State of a policy to encourage economic growth is contrary to the principle according to which
the State should remain neutral as regards people’s varying
concepts of what the good life should be (Bonin, 1997). The
third states that growth is futile, if not counter-productive,
from the point of view of really worthwhile conceptions of
the good life. A fourth argument considers that growth, in
so far as it mobilises large amounts of physical resources,
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
would not be sustainable at the current rate. Each of these
four arguments deserves closer scrutiny, both on their factual
assumptions and their normative plausibility. However, it
should be stressed that intergenerational egalitarianism as developed here presents an argument which differs from those,
notwithstanding the fact that it does refer to a concern for
justice as do the first two “anti-growth” arguments outlined
above.
It is also clear now that the conclusions of an egalitarian
theory do not converge, in the steady-state phase, with those
of for instance, indirect reciprocity. Furthermore, there is
another significant angle from which the proposed convergence is absent. This becomes clearly apparent if we consider a future natural phenomenon (e.g. an earthquake) negatively impacting the fate of the next generation. From an intra-generational point of view, a destructive earthquake must
give rise to compensation from those who did not suffer its
effects, so as to mitigate as much as possible, the negative
consequences for the unlucky few of a phenomenon they
were not responsible for. For a luck egalitarian, any disadvantage arising out of circumstances beyond people’s control should give rise to compensation from the rest of society. A congenital handicap or a particular mother tongue
are characteristics which are unquestionably circumstances
affecting those concerned. A luck egalitarian would immediately add however that if disadvantages arise out of people’s
own choices, their costs should be borne in principle by the
very people who made such choices. The debate in France
on local mountain communities having to foot the bill for
rescue missions to save people practising dangerous sports,
or the debate in Austria concerning the non-reimbursement
of hospital expenses for alcoholic coma induced by particular drinking habits in the younger population, clearly point in
the direction of practices which could well be viewed by an
egalitarian as the result of a choice. In such cases, it would
not be society’s duty to shoulder the burden of its cost (on
choice/circumstance: Dworkin, 2000).
How can we transpose this choice/circumstance distinction into the intergenerational field? Let us go back to our
previous example. If we were able – by extraordinary means
– to predict the occurrence and magnitude of such future
earthquakes and if we were able to demonstrate that the next
generation will be particularly affected by them although, we,
the current generation, would not be affected in the slightest,
the current generation would then be under a savings obligation so as to ensure that, as a result of these earthquakes,
the next generation does not find itself in more unfavourable
circumstances than the current one. This obligation to save
arises out of a very different logic from one based on utilitarianism or the one included in the accumulation phase of the
egalitarian theory. But above all, it does not seem for example, that an indirect reciprocity approach could ever compel
us to transfer more to the next generation than what we received from the previous one.
www.surv-perspect-integr-environ-soc.net/1/39/2008/
A. Gosseries: Theories of intergenerational justice: a synopsis
47
Table 1. Synopsis of the various theories of intergenerational justice.
Indirect reciprocity
Utilitarianism
Lockean proviso
Rawlsian Egalitarianism
Egalitarianism revisited
Brundtland’s Sufficientarism
9
Savings
Dissavings
Authorised
Mandatory
Authorised
Phase 1: Mandatory
Phase 2: Authorised
Phase 1: Mandatory
Phase 2: Prohibited, unless
...
Authorised, unless . . .
Prohibited
Prohibited
Prohibited, unless . . .
Prohibited
Brundtland’s sufficientarianism
We are now well prepared to support the assumption that
Brundtland’s definition of sustainable development would
not be a sufficient safeguard for intergenerational justice. As
mentioned above, development is only said to be sustainable
if it “Meets the needs of the present without compromising
the ability of future generations to meet their own needs”
(WCED, 1987:53). Contrast this formulation with Daly’s,
according to which “. . . the basic needs of the present should
always take precedence over the basic needs of the future but
the basic needs of the future should take precedence over the
extravagant luxury of the present” (Daly, 1996:36). Brundtland’s reference to the concept of need can admittedly be understood in its broader or narrower meaning. To our mind,
the most appropriate interpretation is that of “basic needs”.
But even with a less restrictive version, there is still in such
a definition the idea that once everyone’s needs are covered,
fairness does not require any further redistribution. As long
as everyone’s basic needs are covered, this “sufficientarianism” based on the satisfaction of needs would not demand,
for example, that a person born with a missing finger due to
genetic malformation, should be receiving compensation if
that missing finger does not prevent him from satisfying his
basic needs (on sufficientarianism: Casal, 2007).
In the view of a luck egalitarian, the residual injustice
following Brundtland’s sufficientarianism in that case, is
twofold. First, it authorises a possibly significant degree of
dissavings as long as it is compatible with the capacity of the
next generation to provide for its own needs. Second, by authorising generational savings – that is as long as it does not
compromise the capacity of all the members of the current
generation to satisfy their own needs, it is not responding to
the egalitarian requirement for prohibiting savings on principle out of concern for the least well off in our own current
generation.
Let us be quite clear: this is not an internal criticism of
Brundtland’s theory. Furthermore, if space permitted, we
could certainly try and demonstrate with far greater subtlety
www.surv-perspect-integr-environ-soc.net/1/39/2008/
Phase 1: Prohibited
Phase 2: Prohibited, unless
...
Authorised, unless . . .
the extent to which Brundtland’s report probably opens the
way to alternative interpretations. Nevertheless, what is of
importance here, is that those who consider that luck egalitarianism is the most plausible theory of justice when dealing with intragenerational allocation issues have no reason to
abandon this theory when moving on to intergenerational issues. Egalitarians should certainly reject Brundtland’s theory
as being insufficient.
10 Conclusion
This short paper is based on a set of simplifying assumptions. We did not, for example, consider the composition
of the basket of goods to be transferred to the next generation (e.g. can the oil or the biodiversity that we are squandering be replaced by motorways or cultural assets?). We only
broached on a very general level the issue of equitable intergenerational transmission, on the basis of two categories
(savings/dissavings) and three modalities (prohibition, authorisation and obligation). Nevertheless, this synopsis has
allowed us to highlight two important points. Firstly, using
a very simplified framework, one can see in outline some
very different operational principles. We can observe for example that both the utilitarians and the egalitarians (in the
accumulation phase and in certain limited assumptions in the
steady state phase) include the generational savings obligation in their theories, albeit for very different reasons. We can
also see that the dissavings prohibition option is to be taken
seriously by egalitarians in the steady state phase. Finally,
are also worth noting the departures from the dissavings prohibition that are present in the Lockean or sufficientarian approaches. Secondly, it is now obvious that the standard approach to sustainable development as Brundtland views it is
by no means the only option. And it is clearly problematic
on two counts for an egalitarian.
In point of fact, these theories of justice provide resources
for thinking not just along different lines, but also for broaching the issue of intergenerational justice through the prism of
various logics which, if they are understood in depth, can
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
48
generate a multiplicity of implications. This is particularly
true once the ultra-simplified world represented here is enriched with a set of additional variables to bring it closer to
the real world. Each of these theories can respond differently
for example to demographic fluctuations, the case of the indirect reciprocity view being probably the most emblematic
on this count. For certain theories, population changes would
modify what we owe to the next generation, whereas for others, it would in no way alter the magnitude of our intergenerational obligations. Similarly, the degree to which descending intergenerational altruism turns out to be significant will
affect, to a greater or lesser degree, our obligations to the
next generation depending on the theory which is adopted.
Generational overlap (or its absence) is also more significant
in some approaches than in others, particularly in the case
of mutual advantage theories. And the fact that a previous
generation has, or has not, fulfilled its own obligations (noncompliance issue) will affect, also in varying degrees, the
obligations that each of these theories places on the current
generation. It is illuminating in this regard to have in mind
how a Lockean proviso tackles the disregard, by a generation
previous to our own, of its intergenerational obligations; and
how an egalitarian theory can take on board the risk of noncompliance with its intergenerational obligations by one of
the generations that comes after us.
As we can see, taking the standard theories on justice seriously is fairly enlightening as to the various possible ways
of tackling the issue of our intergenerational obligations. To
be sure, there is still a long way to go before we can define
the precise contours of these obligations... and set up the institutions to enforce them.
Acknowledgements. This paper is a revised version of Gosseries
(2005). We particularly wish to thank B. Gagnon, M. Fleurbaey
and P. Savidan for their comments during the preparation of this
paper, the original French version of which is forthcoming in
Raison publique (2008). We are also much grateful to Evelyn
Apaire Van Gelder for her translation from French.
Edited by: G. Maingauy
References
Arneson, R.: Lockean Self-Ownership: Towards a Demolition, Political Studies, 39(1), 36–54, 1991.
Arrhenius, G.: Mutual Advantage Contractarianism and Future
Generations, Theoria, 65(1), 25–35, 1999.
Barry, B.: Justice as Reciprocity, in: Liberty and Justice, Oxford,
Oxford University Press, 1989.
Birnbacher, D.: Can discounting be justified?, International Journal
of Sustainable Development, 6(1), 42–53, 2003.
Bonin, P.-Y.: Neutralité libérale et croissance économique, Dialogue, 36, 683–703, 1997.
Bränvall, M.-L., Bindler, R., Emteryd, O., and Renberg, I.: Four
thousand years of atmospheric lead pollution in northern Europe:
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008
A. Gosseries: Theories of intergenerational justice: a synopsis
a summary from Swedish lake sediments, J. Paleolimnol., 25,
421–435, 2001.
Burke, E.: Reflections on the French Revolution, Cambridge
(Mass.): The Harvard Classics, 1909–14.
Casal, P.: Why Sufficiency is Not Enough, Ethics, 117(2), 296–326,
2007.
Cosandey, D.: La faillite coupable des retraites, Comment nos assurances vieillesse font chuter la natalité, Paris, L’Harmattan,
2003.
Cowen, T. and Parfit, D.: Against the Social Discount Rate, in: Justice between age groups and generations, edited by: Laslett, P.,
and Fishkin, J., New Haven/London, Yale University Press, 144–
161, 1992.
Daly, H.: Beyond Growth, The economics of sustainable development, Boston, Beacon Press, 1996.
De Shalit, A.: Why Posterity Matters. Environmental policies and
future generations, London, Routledge, 1995.
Diamond, J.: Collapse. How societies choose to fail or survive,
Viking Books, 2005.
Dworkin, R.: Sovereign Virtue. The Theory and Practice of Equality, Cambridge/London, Harvard University Press, 2000.
Elliot, R.: Future Generations, Locke’s Proviso and Libertarian Justice, Journal of Applied Philosophy, 3(2), 217–227, 1986.
Gaspart, F. and Gosseries, A.: Are Generational Savings Unjust?,
Politics, Philosophy & Economics, 6(2), 193–217, 2007.
Gauthier, D.: Morals by agreement, Oxford, Clarendon Press, 1986.
Gilfillan, S. C.: Lead Poisoning and the Fall of Rome, J. Occup.
Med., 7, 53–60, 1965.
Gosseries, A.: De la nécessité de distinguer protection de
l’environnement, conservation de la nature et conservation de la
biodiversité, L’exemple de l’introduction d’une sous-espèce noneuropéenne d’espèce protégée (note under CJCE, C-202/94),
1997, Revue juridique de l’environnement, 22(2), 220–227,
1997.
Gosseries, A.: L’éthique environnementale aujourd’hui, Revue
philosophique de Louvain, 96(3), 401–405, 1998.
Gosseries, A.: Penser la justice entre les générations, Paris, AubierFlammarion, 2004a.
Gosseries, A.: Historical Emissions and Free-riding, Ethical Perspectives, 11(1), 36–60, 2004b.
Gosseries, A.: The Egalitarian Case Against Brundtland’s Sustainability, GAIA, 14(1), 40–46, 2005.
Gosseries, A.: Dette générationnelle et conceptions de la
réciprocité, in: Finances publiques et redistribution sociale,
edited by: Pellet, R., Paris, Economica, 367–391, 2006a.
Gosseries, A.: Egalitarisme cosmopolite et effet de serre, Les
séminaires de l’IDDRI (Paris), 14, 18–23, 2006b.
Gosseries, A.: Radiological Protection and Intergenerational Justice, in: Ethics and Radiological Protection, edited by: Eggermont, G. and Feltz, B., Louvain-la-Neuve, Academia-Bruylant,
167–195, 2008.
Heath, J.: Intergenerational Cooperation and Distributive Justice,
Can. J. Phil., 27(3), 361–376, 1997.
Jaurès, J.: Etudes socialistes, Paris, P. Ollendorf, 1902, http://
gallica.bnf.fr/ark:/12148/bpt6k886633, last access: April 2008.
Jefferson, Th.: Letter to James Madison (6 sept 1789), Disponible
sur: http://odur.let.rug.nl/∼usa/P/tj3/writings/brf/jefl81.htm, last
access: 14 May, 2008.
www.surv-perspect-integr-environ-soc.net/1/39/2008/
A. Gosseries: Theories of intergenerational justice: a synopsis
Lessler L.: Lead and Lead Poisoning from Antiquity to Modern
Times, Ohio J. Sci, 88(3), 78–84, 1988.
Locke, J.: Two Treatises of Government and A Letter Concerning Toleration, edited by: Shapiro, I., New Haven/Londres, Yale
University Press, 1690 (2003).
Márai, S.: Les Confessions d’un bourgeois, Paris, Albin Michel (Le
Livre de Poche), 1993.
Maréchal, J.-P. and Quenault, B. (Eds.): Le développement durable,
Une perspective pour le XXIè siècle, Rennes, PUR, 2005.
Ponting, Cl.: A Green History Of The World. The Environment and
the Collapse of Great Civilizations, New York, Penguin, 1993.
Rawls, J.: A Theory of Justice (revised edition), Oxford/New York,
Oxford University Press, 1999 (Orig. 1971).
Smart, J. J. C. and Williams, B.: Utilitarianism. For and Against,
Cambridge, Cambridge University Press, 1973.
Steiner, H.: An Essay on Rights, Oxford, Blackwell, 1994.
www.surv-perspect-integr-environ-soc.net/1/39/2008/
49
Stern, N.: The Economics of Climate Change: The Stern
Review, Cambridge, Cambridge University Press, also available at: http://www.hm-treasury.gov.uk/independent reviews/
stern review economics climate change/stern review report.
cfm, 2007.
Vallentyne, P. and Steiner, H. (Eds.): Left Libertarianism and its
Critics: The Contemporary Debate, New York, Palgrave, 2000.
Wade-Benzoni, K. A.: A Golden Rule Over Time: Reciprocity
in Intergenerational Allocation Decisions, Academy of Management Journal, 45(5), 1011–1028, 2002.
Waldron, J.: Enough And As Good Left For Others, Philosophical
Quarterly, 29, 319–328, 1979.
WCED (World Commission on the Environment and Development): Our Common Future, Oxford/New York, Oxford University Press, 1987.
Wolf, C.: Contemporary Property Rights, Lockean Provisos and the
Interests of Future Generations, Ethics, 105(4), 791–818, 1995.
Surv. Perspect. Integr. Environ. Soc., 1, 39–49, 2008