SciELO - Scientific Electronic Library Online

 número21A dimensão do cuidar e a ressignificação do espaço público no pensar e agir de Maria de Lourdes PintasilgoMaria de Lourdes Pintasilgo Primeira-Ministra do V Governo Constitucional. Em busca das reacções na imprensa índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados




Links relacionados

  • Não possue artigos similaresSimilares em SciELO


Ex aequo

versão impressa ISSN 0874-5560

Ex aequo  n.21 Vila Franca de Xira  2010


Caring for Future Generations and Biodiversity: Earth Ethics and Some Implications for Structurig the Global Public Domain


J. (Hans) B. Opschoor *

Institute of Social Studies, Haya



In this paper Hans Opschoor considers how society can extend the concern over the common good to include not only future generations of humans, but also other parts of Earth’s biodiversity. He explores some moral philosophy and/or ethics based approaches to this, in a context of rights and responsibilities or duties that humans have (or could consider having!), and see how that should influence the way societies today shape their public spaces.

Keywords biodiversity, care, global ethics, rights, responsibility.



O cuidado com as gerações futuras e a biodiversidade: ética da terra e algumas implicações para estruturar o domínio público

Neste artigo, Hans Opschoor pretende mostrar a maneira como as sociedades podem aumentar a sua preocupação em relação ao bem comum, incluindo aí, não apenas as futuras gerações, mas também outras dimensões da biodiversidade terrestre. Fá-lo explorando algumas linhas de desenvolvimento da filosofia moral e da ética num contexto de direitos e responsabilidades ou deveres que os humanos têm ou deveriam ter e considera a influência que elas deveriam ter sobre o modo como as sociedades configuram o seu espaço público.

Palavras-chave biodiversidade, cuidado, ética global, direitos, responsabilidade.



Soigner les futures générations et la biodiversité : éthique de la terre et quelques implications pour structurer l’espace publique

Dans cet article, Hans Opschoor s'attache à montrer la manière dont les sociétés peuvent étendre leur préoccupation concernant le bien commun, en incluant non seulement les futures générations humaines, mais également d'autres dimensions de la biodiversité terrestre. Pour ce faire, il explore certaines démarches de la philosophie morale et de l'éthique dans un contexte de droits et de responsabilités, ou devoirs, que les humains ont (ou devraient avoir), et considère l'influence qu'elles devraient avoir sur la manière dont les sociétés configurent leur espace publique.

Mots-clés biodiversité, souci, éthique global, droits, responsabilité.




Homo sapiens is one amongst millions of species (estimates range from a minimum of 2 million to guesstimates as high up as 100 million) all sharing the planet Earth. While aware of other planets, Homo sapiens must consider itself bound to Earth for the foreseeable future. We should look at our species not as a set of populations of individuals, but as organized in communities and societies at different levels (ranging from local via national – i.e. states – to global) that at each of these levels interact with other elements of the Biosphere. Global society has begun to understand that and is concerned about biospheric constraints to its development (think of climate change or depletion of fossil fuel reserves). It discusses «our common future» (WCED, 1987) and tries to design ways to ensure we have one – a livable one, preferably a good one for all: sustainable development. The latter requires «caring for the future» (IC, 1996).

People – the individual members of the human species – find themselves in public spaces where they interact to deal with issues of common interest. In this era of globalization and global change, the so-called global public goods (peace and security, but also: a healthy environment, the provision of resources for human welfare, equity or fairness in access to resources and social security for all) are of particular importance in endeavors to substantiate the common good. Cutting a few corners rather rapidly, I would like to echo here that «[i]n an increasingly interdependent world where our major challenges can only be addressed in and through international cooperation, shared values and global ethics are essential» (Rockefeller, 2007). In this paper I will, from this vantage point, consider how society can extend this concern over the common good to include not only future generations of humans, but also other parts of Earth’s biodiversity (which I will take as being represented by «other species»). I will – in a rather multi- or interdisciplinary way – explore some ethics based approaches to this, in a context of rights and responsibilities or duties that humans have (or could consider having!), and see how that should influence the way societies today shape their public spaces.

Of course the notion of ‘common good’ in the moral sense is different from that of global public goods – yet the position taken here is, that the latter are a relevant component of the former and can be regarded as part of the ‘substance’ (if one wishes) of the common good. Likewise, the public domain is not identical to structures of governance – yet such structures are crucial is we wish to understand (or alter) the provision of public goods or, more generally, societal action and the realization of social values.


1. Towards a Global Ethics: elements of a conceptual framework

Before discussing some proposed ‘global ethics’ (in Section 2) and how they might play out in the global public space (Section 3) I want to present some concepts and ideas – taken from the social as well as the moral domains – that provide background and structure to these proposals. I will sketch a particular social philosophic perspective on the evolution of the public domain (1.1) and recognise the ethics of care as one basis from which to articulate a desirable further development in that domain (1.2). Then I discuss to whom this notion of care extends (1.3) and how care relates to concepts such as ‘rights’ (human rights in particular) and duties (1.4). In 1.5 I highlight biodiversity as a particular set of members of the community of life that the ethics of care might apply to.


1.1. An extended Habermasian Perspective

Habermas (1981) describes society as composed of people ideally co-ordinating their activities in open communicative processes where they experience their societies as their own ‘lifeworlds.’ Though Habermas primarily regards lifeworlds primarily in terms of social, cultural and moral aspects, I suggest it can be used in relation to socio-economic and political features and co-ordination at that level as well and in what follows I will use this extended interpretation. Modernization has meant that increasingly these communicative processes have become replaced (crowded out) by emerging ‘rational’ autonomous systems co-ordinating societal action: the state and the market. These systems operate on the basis of their own (functionalist) normativity (e.g.: the economic system being geared towards efficiency) regardless of (substantive) considerations and views from the life-world perspective. If these systems dominate the life world, Habermas speaks of ‘colonization’ of the lifeworlds by these systems. The notion of ideally autonomous lifeworlds at the political level corresponds with that of a report by an international committee chaired by Maria de Lourdes Pintasilgo: « Caring for the Future» (IC, 1996) in which sovereignty in the public space is said to ultimately rest with the people.

In the process of globalization as we see at work in the world, these two systems (the economic and the political one) appear to merge into one system, dominated by economic processes and rationales, while political forces (superpower and conglomerates of states such as the G-8 excepted) are on the decline. That leaves the life-worlds effectively occupied by largely economic forces and powers2. These have reached not only into the lifeworlds of people, but have penetrated also into the non-human or non-social part of the biosphere, the ecosphere, colonizing and exploiting that sphere with the same a-morality that governs the economic imprint on human lifeworlds. I will argue that non-human elements of the biosphere are entities that humans have moral duties towards, thus making this colonisation of their ‘lifeworlds’ (perhaps better referred to as ‘habitats’) even more of an issue.

These processes of colonisation manifest themselves in rising global inequality, and enhanced risks of unsustainability. These new challenges at the global level and especially underlying driving force of globalization demand «countervailing powers» (to quote Galbraith) as well as a countervailing social philosophy. In his paper I will look at some «countervailing philosophies» in particular (for my views on countervailing powers: see Opschoor 2003). More precisely, I will review some attempts at articulating new ethics dealing with the global concerns that have become manifest in the decades behind us. If taken up my socially relevant forces they could become significant in future attempts at restructuring the public domain – they already are in discourses about the desirability of such attempts.


1.2. Ethics of Care

Ethics has positive and normative branches. Normative ethics traditionally has two main divisions: teleological ethics and deontological ethics. The former (named after the Greek telos, for purpose or objective) operates in the perspective of some a prioristic objective like ‘the greater social utility, or a maximum of human happiness; examples are utilitarianism and hedonism. The latter (named after the Greek deon, for duty) by-passes intentions, looks at behaviours and tries to derive rules of conduct and processes to make people behave according to their duties (e.g. Kant’s ‘categorical imperative’ or Rawls’ ethics of justice as fairness).

A more recent new branch on the tree of normative ethics is: the ethics of care, coming in from feminist theories (see e.g. Gilligan, 1982 and Noddings, 2005), but with much wider potential implications than in the gender field as such. The ethics of care emphasize the importance of relationships, where agents respond to an «other» or «others» in their terms. The ethics of care has been said to be based on the recognition of: (i) the interdependence in principle of individuals, and (ii) the proposition that those particularly vulnerable to the impacts of choices made by people deserve extra consideration. In Caring for the Future (IC, 1996) Maria de Lourdes Pintasilgo sees ‘care’ as a notion providing the foundation for a «new humanism» that would be able to effectively address the social, economic and ecological challenges the world’s population is – and will be – facing when searching for (more) «quality of life». The report proposes that quality of life can be understood only by taking into account (inter alia) the «caring capacity of humankind». Caring is described as meaning: to value, to love, to attend to, to nurse and nourish; it is the opposite of «indifference». The capacity to care defines people as human beings and is the cement of society. Caring for ourselves, for each other, and for our environment is the foundation upon which the sustainable improvement of the Quality of Life is founded. The report sees the caring capacity eroding and tries to re-invigorate it and apply it to the world of politics.


1.3. Moral Community/Moral Environment

Who are the «others» (or which are the categories of others) that deserve this extra consideration? That question brings us to the concept of the moral community. In its widest sense a (or the) «moral community» is the set of those persons and/or non-personal entities to whom we attribute ethical significance: those whose interests are consciously taken into account when decisions and/or evaluations of situations and actions are made. The moral community thus defined may range from family and friends, to all living things (the ‘community of life’); in-between positions would include those who share our gender or race, class, profession, religion, nationality, and/or all humans (those alive today, and possibly future generations).

The notion takes on practical meaning especially in situations of scarcity where society has to make choices: when resources are limited and we cannot let everyone make an equal claim to them. We must weigh the various claims against each other, considering the resources we have to respond and the duty we owe to those who call on us. Membership of a moral community implies the possession of rights. For some moral philosophers each person has equal dignity and therefore has the same entitlement as anyone else (others may defend positions giving different weights to different subcategories, where kinship ties, cultural affinities or even mere distance might account for the weights applied). Some argue further that moral recognition and corresponding responsibilities should extend not only to all people but also to future generations – possibly even to animals and plants (or biodiversity in general). Entities regarded as being beyond the moral community get zero weight in decisions and evaluations.

Others use a much more restrictive definition and hold that a moral community is a group of entities who live in relationship with each other and use and understand moral concepts and rules. This would effectively restrict membership to human beings. Human beings can respect each other and each other’s autonomy. Non-human entities lack the capacity for moral judgements and that is then said to imply that they cannot have rights. It may be noted that this narrower concept of moral community seems to correspond to Habermas’ life world of people. Formally speaking, future generations cannot be part of a community as there cannot be any reciprocity.

If one is ready to go beyond the notions of self-awareness, and conscious relationality, then a set of entities can be discerned for which individuals or social groups or even societies may feel moral obligations – even in an asymmetric and un-reciprocal way. To distinguish these from the moral community as a set of living human beings, this set could be referred to as the ‘moral(ly relevant) environment’. The moral community (if taken to be a category exclusively reserved for sets of humans) would then be part of this moral environment. This would at least enable bringing into the moral horizon categories such as future generations and non-human living organisms or species. And that is what I want to do – in the setting of our search for global ethics. What this amounts to is the attribution of value or moral relevance to these categories or their members, by those who are in positions to attribute such values: people living, debating and voting today and feeling a responsibility or a duty to care for those other generations and species.


1.4. (Human)Rights and Responsibilities

In an equity-based perspective members of a moral community (and of the moral environment) can be said to have rights; in a perspective of care, members can be seen as having duties towards others.

Human Rights

Human rights are rights of humans. Human beings have needs – some of these very basic ones – and the (normative) view that they should be met, i.e. their legitimisation, provides the ground for attempts to transform them into rights (Gaay Fortman and Klein Goldewijk, 1999: 48). The main rationale of human rights is that they protect individuals from asymmetries in relationships (often power-based) between individuals and societal institutions – the state, in particular. Within human rights a distinction is made between: (i) civil and political rights of individuals, (ii) social, economic and cultural rights of individuals, and (iii) collective rights or group rights (see table 1)3:


Table 1 - An Overview of Human Rights


There is a view that there are categories beyond the present generation of humans that also have needs. To begin with, as the concept of ‘humanity’ in principle encapsules all generations (past, present and future), the entitlements of future generations should be recognised. Present day’s international law allots too few rights to future generations (Schrijver, 2006). Secondly, by definition human rights do not extend to other species or life forms. If the view is held that needs of these categories should be met as well, then one might say that they are allotted rights as well. However, if the notion of rights holding is restricted to entities that are capable of articulating their rights as claims, then future people and other species would drop out. What cannot be denied, though, is that these categories do have interests, or stakes, that can be jeopardised by actions of people. So, looked at from the vantage point of needs and interests, rights can rest with (or be given to) living humans (e.g. human rights) and with others.

Duties, responsibility, care

Notions such as entitlements, responsibilities and care are to be differentiated, but they are related in sometimes complex ways.

Dealing with many issues arising from globalisation and economic expansion such as the issues of unsustainability on which I focus here, does require international cooperation, shared values and ‘global ethics’. These values should commit society and its members to the ‘common good’ (or ‘public interest’) and replace a common ethic of individual rights with an ethic of the common good» (Gaay Fortman and Klein Goldewijk, 1998:82). The latter, it is increasingly felt (and I adopt that position here), is to include a concern over quality of life of human beings now and in future (IC, 1996) and over other species, and calls for an ecologically informed and elaborated global ethics – where rights are provided with a complementary notion: that of duties or responsibilities and extending to all in the ‘moral environment’. Presently alive human actors may adopt the normative position that they are duty holders with a duty to uphold entitlements where (essential) needs of others in the moral environment are not met. Such duties could be seen as a reflection of a deeper feature the responsibility one feels (or is supposed to feel) for others in the moral environment. That responsibility may stem from a sentiment of care for these other members of the moral environment are at stake. In care-driven bahaviour and choices society may seek to ensure that, on way or another, needs of these less endowed members of the moral environment are, or will be, met. As Goudzwaard and De Lange (1995) observe: «Care is an authentic element of the oldest definitions of the Greek word oikonomia, economy». And it should give rise to the allocation of financial resources and labour to activities in the social and ecological domains, nationally and internationally. We see in the richer countries that this has indeed happened; however, there is an emerging trend of care systems to dwindle and disappear4. At a political level, bringing ‘care’ to effect may ultimately imply that needs and needsbased claims are to be enshrined in rights, and provision-oriented social and economic structures.


1.5. Biodiversity: intrinsic and instrumental values

The natural environment – the ecospheric part of the biosphere (defined as the number and variety of genes, species and ecosystems) – consists of biotic and a-biotic elements, and processes operating between them. It provides human beings with economically directly relevant resources – biotic and a-biotic – and with sinks to absorb the emissions and waste humans dispose of as a result of their use of natural resources. The biosphere can be seen as the base of a series of so-called ‘life-support systems’: the ecological processes that shape climate, clean air and water, regulate water flow, recycle essential elements, create and regenerate soil, and keep the planet fit for life. Nature is related to humans and human systems in at least a functional, instrumental way: it serves human interests, as it is a source of utility.

The biosphere also provides life support services to other members of the community of life: other species, etc. Humans share a common destiny with other species in that all species will have to make it on this planet – as long as evolutionary dynamics enable that. When considering these species, the functional or instrumental aspects of natural systems to humans do not exhaust the value(s) of nature or its other (i.e. non-human) elements. There are intrinsic aspects of value – value according to a right to exist of an ecosystem or a species (or a population or an individual), apart from whether or not there is functionality in terms of human interests. This value can be seen as based in the fact that we are dealing with elements that are part of ‘creation’, or as rooted in the mere existence of the element of nature concerned. Table 2 captures the essence of categories of value one may discern. Along the rows different categories of stakeholders are shown, and in the columns the different types of values. Some argue that categories 5 and 6 are nonexistent: values are properties assigned to entities by humans and by humans alone, they would claim. Yet, one could envisage that in order to acknowledge rights such as underlying 6, societies would set aside territory under their jurisdiction to allow viable populations of certain species enough land and resources to survive and evolve. More or less likewise, it could be argued that the categories 3 and 4 – even though they could exist in terms of their having a background in (potential) human mental calculus – are virtual rather than real, since, by definition the individuals allegedly allotting such values do not yet exist.


Table 2 - Types of Stakeholders and different types of Values


The realization of these intrinsic values and existence ‘rights’ engenders notions of care and responsibility, translating (at least: potentially) into duties towards these other life forms – these other stakeholders in a community of life, or moral environment. What the weights are that these various stakeholders have, is another matter – one in which power asymmetries and different appreciations of responsibility and care are crucial, of course.

Let us first look at what he world has agreed on in relation to non-human species, or biodiversity in general. The UN Convention on Biodiversity (CBD, 1992) in its preamble affirms the intrinsic value of biological diversity, and then goes on to also assert an awareness of the value of biodiversity (and its components) in e.g. ecological, social, economic, cultural and esthetic respects (i.e. the instrumental value or the functions of biodiversity). CBD also recognizes the significance of biodiversity for evolution and the preservation of the systems supporting the biosphere5. States are held responsible for the preservation of «their» biodiversity and the sustainable use of their biological resources. States are to develop national strategies for the preservation and sustainable use of biodiversity in the interest of current and future generations, and to take action, «in accordance with their own circumstances and possibilities», or «as far as possible and appropriate». Lastly, there is a procedure for disputes between states on the interpretation or application of the CBD, ending with putting the dispute before the International Court of Justice. We see here an intention to conserve biodiversity, an ultimate subjection of biodiversity use to the interests of humans (now and in future), an acknowledgement of the sovereign right of states to exploit their own resources as long as the rights of other states are not jeopardized, a constraint on rights that we also observed in relation to ESC (human) rights: they were to be honoured as long as available resources allow it – and biodiversity protection is a duty as far as possible. Notions such as these open doors to all kinds of neglect and ignorance on the ground that resources unfortunately are unavailable. Yet, there are possibilities to address neglect – at least from one state to another, and in cases where neglect extends to damage done to other states’ biodiversity resources. I know of no action (arbitrage or a court case) yet, under CBD.

Another document relevant in the context of this conference is Caring for the Future (IC, 1996). It regards ‘biodiversity’ to be an immediate constituent of Quality of Life. It is presented as important for supply food, pharmaceutical products, and aesthetic values – very much in line with the instrumental analysis in WCED 1987 and CBD 1992. The report is vague on the intrinsic values of biodiversity, but does state that recognition is needed of fact that human being share «a common destiny with nature, that our lives depend on and are interwoven with Nature’s basic ingredients of air, water, land and trees» (p. 38). What that recognition should entail, is left undiscussed. In the next section we will look at some recently proposed ‘global ethics’ that do explicitly address these aspects.


2. Global Ethics Systems – some concrete examples

How do global problems-inspired ethics deal with rights and responsibilities for other humans now and in future, and for other non-humans? We will take a brief look at the contours of five such systems: «Global Ethics», the Earth Charter, a proposed Declaration of Human Responsibilities, the Millennium Declaration and «Caring for the Future».


2.1. Declaration Towards a Global Ethics

The ‘Declaration towards a Global Ethic’ is a result of a project led by theologian Hans Küng. It was endorsed by the Parliament of the World’s Religions in 1993.

Following a preamble spelling out the social, ecological and security dimensions of a world «in agony», the substantive part of the declaration asserts: interdependency and hence respect for the community of living beings and for the planet and its preservation; (individual) responsibility for all decisions, actions and failures to act; generosity, based on the notion of ‘the human family,’ equal partnership between men and women, absence of domination or abuse; a ‘culture of non-violence, respect, justice and peace’; the need to strive for a social and economic order in which all have an equal chance to reach their full potential as human beings. And it ends with a pledge of commitment to this global ethic and an invitation to all people, whether religious or not, to do the same.

A responsibility and duty is proposed, related to «the welfare of all humanity and care for the planet Earth» (Part I). In Part II the Golden Rule is reiterated (‘what you wish to be done to yourself, do to others’) and hence respect for life and dignity, individuality and diversity, patience and acceptance, a culture of solidarity and relatedness. In Part III four «irrevocable directives» are elaborated, including:

(i) Commitment to a culture of non-violence and respect for life including respect for life of non-human life forms;

(ii) Commitment to a culture of solidarity and a just economic order – which is seen as requiring structural change and institutional reform.

The passages related to future human beings and other species and entities are worth mentioning in some detail. «A human person is infinitely precious and must be unconditionally protected. But likewise the lives of animals and plants that inhabit this planet with us deserve protection, preservation and care. … As human beings we have a special responsibility – especially with a view to future generations – for Earth and the cosmos, for the air, water, and soil. … the dominance of humanity over nature and the cosmos must not be encouraged. Instead we must cultivate living in harmony with nature and cosmos». And: «We must utilize economic and political power for service to humanity instead of misusing it in ruthless battles for domination. We must develop a spirit of compassion with those who suffer … We must cultivate mutual respect and consideration….».


2.2. The Earth Charter

The Earth Charter is the result of a worldwide participatory process (including religious organizations) of consultation staring already before the Earth Summit of 1992 (Rio de Janeiro); it is an attempt to articulate a new charter to guide states in the transition to sustainable development. Subsequently, meetings were held leading up to an NGO-supported Earth Charter endorsed in 1992. In 1994 a new Earth Charter Initiative aimed at the UN; a final version was launched in 2000. To date the Earth Carter has been endorsed by over 2000 organizations, is supported by UNESCO’s General Conference, 2003, and has received acknowledgements from a range of governments. It came close to obtaining recognition at the 2002 World Summit on Sustainable Development.

The Earth Charter’s principal commitments are:

(i) respect for Earth and life in all its diversity;

(ii) care for the community of life with understanding, compassion and love;

(iii) building democratic societies that are just, participatory, sustainable, and peaceful;

(iv) securing Earth’s bounties and beauty for present and future generations;

(v) protect and restore the integrity of Earth’s ecological systems with special concern for biodiversity and the natural processes that sustain life;

(vi) prevent harm to the environment and apply a precautionary approach.

Some 10 further points are specified that form necessary practical sets of principles, including: adoption of patterns of production, consumption and reproduction that safeguard Earth’s regenerative capacities, human rights and community wellbeing; eradication of poverty; ensurance that economic activities and institutions promote human development equitably; strengthen democratic institutions, transparency and accountability, participation and access to justice; promotion of a culture of tolerance, non-violence and peace.


2.3. A Declaration of Human Responsibilities

The world has, since 1948, an agreed Universal Declaration of Human Rights. The so-called Inter Action Council (a body composed of a number of former statesmen, etcetera, including Maria Pintasilgo) in 1997 – almost 50 years later – launched a draft complementary declaration a (proposed) Universal Declaration of Human Responsibilities (UDHR). IAC recognises that a better social order requires a global ethic (agreed values and standards) applied to all people and institutions, and in that ethic rights and responsibilities are both important.

IAC’s proposal is based on recognition that human dignity and human rights requires foundation of freedom, justice and peace, and implies obligations or responsibilities. Persons have responsibilities to treat all people in a humane way; all (and all groups and institutions) are subject to ethical standards, all have responsibility to promote good and avoid evil, the golden rule is reiterated. On that basis IAC advocates, inter alia:

– non-violence and respect for life: every person must be protected; animals and the natural environment also demand protection. All people have a responsibility to protect the air, water and soil of the earth for the sake of present and future generations.

– Justice and solidarity: all people have a responsibility to make serious efforts to overcome poverty and inequality. They should promote sustainable development all over the world.


2.4. The Millennium Declaration

The Millennium Declaration (UNMD), adopted by the UN General Assembly of 8th Sept. 2000, is a statement by the world’s states (or their representatives in the General Assembly), in reaffirmation of the faith in the UN as indispensable foundation of a more peaceful, prosperous and just world (UNMD, 2007: I-1). As such, it is the only formally adopted, broad statement on the collective responsibilities of states for upholding human dignity (the cornerstone of the UDHR and in fact of the UN Charter) equality and equity at the global level. The specific new element is the challenge to ensure that globalisation will become a positive force for the world’s people.

UNMD’s core value include: (a) freedom: the right to a life in dignity, free from hunger, violence, oppression, injustice, (b) equality, (c) solidarity and a fair distribution of costs and burdens of global challenges, (d) respect for nature (that is, a change of patterns of production and consumption towards sustainability). These values must be translated into action, and UNMD distinguishes a number of «key objectives» in this respect, including: (i) peace and security, (ii) development and poverty eradication, (iii) protection of the «common environment», (iv) human rights, democracy and good governance.

Looking more closely at the values discerned, one can see that «respect for nature» includes prudence in the management (sic) of all living species and natural resources, in accordance with the precepts of sustainable development. Only in this way can the immeasurable riches provided to us by nature be preserved and passed on to our descendants. The current unsustainable patterns of production and consumption must be changed in the interest of our future welfare and that of our descendants». And the objective of «protecting our common environment» is articulated in the perspective of avoiding the «threat of living on a planet irredeemably spoilt by human activities, and whose resources would no longer be sufficient for their needs». States «resolve to adopt … a new ethic of conservation and stewardship (which is then elaborated in relation to climate change, forest conservation and management, biodiversity, water resources, etc.).


2.5. Caring for the Future

Maria de Lourdes Pintasilgo has chaired the Independent Commission on Population and Quality of Life (1996) that produced «Caring for the Future» in the wake of WCED on Sustainable Development (1987), UNCED (1992), Cairo (UN Conference on Population and Development, 1994). The report aimed at providing a fresh vision on the challenges (social, ecological, economic) that are posed by population dynamics in a globalizing world, and at operationalising that vision into policy proposals in search of (more) quality of life. Maria de Lourdes Pintasilgo wrote a preface, from which the following points of departure are taken:

– sustainability as a basic principle in dealing with nature;

– absolute poverty as a scandal;

– irrationality of consumption patterns;

– quality of life for all as a societal objective.

Clearly, the notions of quality of life, sustainability and poverty as a scandal are very similar to the value basis of the global ethics we saw in earlier paragraphs.

The report proposes that Quality of life can be understood only by taking into account the carrying capacity of the earth and the «caring capacity of humankind». The latter notion we have discussed before. The Earth’s Carrying Capacity is defined as: the maximum sustainable load that humankind can impose on the environment before it loses its capacity to support human activity. And quite explicitly: these limits are to be respected – which gives rise to duties that are not further articulated in detail.

The notion of quality in first instance is restricted to the life of humans; it is a notion that reflects the level of satisfaction of their material, social and psychological needs. The report sees these needs as essentially identical over generations. Quality of Life is extended to also include concern over the future of humanity – this then brings in the element of duties. The future of humanity requires society’s ‘sustainability’, as an element of security (political, socio-economic). Security implies sustainability i.e. there is a need to keep our natural stocks in tact (incl. biodiversity). Here again, the value of biodiversity is seen as instrumental more than anything else, and duties related to it are recognized primarily (if not exclusively) in terms of ensuring and preserving the provision of these instrumental values.


2.6. Comparisons

In a sense, all systems described above address human beings – people that are active in today’s public arenas and are the relevant moral agents. They do differ though in the extent to which they are human-centred. Caring for the Future, the Declaration of Human Responsibilities and the Millennium Declaration clearly are anthropocentric, also at the level of the values they articulate. They do – albeit in different levels of detail and on varying grounds – specify duties or responsibilities towards others (other humans/future generations, other life forms) – especially responsibilities to protect other species. Caring for the Future seems least far-reaching in this respect and seems to regard such a responsibility primarily in instrumental terms. Of course, it is explicit in its care for future generations – although here too in the elaboration in the practical part this focus seems to get lost a bit in favour of attention for more immediate concerns.

Global Ethics and Earth Carter have a different orientation: towards care about human welfare AND the planet, and care for Earth, the community of life and human welfare. The wordings are different but the intentions identical. Both also refer more explicitly to other life forms and future generations, and thus cover the complete set of ‘elements’ or ‘stakeholders’ discussed before. There is a difference between the two, in that compared with Küng’s Global Ethics, the Earth Charter adopts an essentially secular perspective, even if it refers to spiritual values and beliefs including religiously based ones.

In terms of scope, the documents clearly differ. The Earth Charter is regarded by its promulgators as a guide to action by individuals, organisations both governmental and non-governmental, and economic agents. As there is little or no analysis of the causes of the abhorrent state of the world, the Declaration towards a Global Ethic cannot become specific as to what it wants in positive terms, in the areas of change. Thus, it very much remains a statement in (and to) the public domain, not a proposal for reforms in that domain. The Global Ethics does have a principle of Social and Economic Justice, which sets it apart from the other ethics, as it speaks of the need of a ‘just economic order’. In relation to the latter, it is illuminating that the Declaration of Human Responsibilities mentions that economic globalisation has led to the globalization of problems. Also Caring for the Future is deeply concerned over issues to do with the type of globalisation the world has seen, and issues to do with economic ‘rationalities’ (see below). A specific new element in the Millennium Declaration is its stating hat it is a challenge to ensure that globalisation will become a positive force for the world’s people. The Millennium Declaration is very much focused on the furthering of equitable and sustainable human development, and speaks of stewardship to express its concern over opportunities for future generations.


3. Turning Global Ethics into Institutions in the Public Space

The ethical declarations and systemic critiques discussed in Section II go quite a way in outlining elements of a «countervailing philosophy». How could these ethics be operationalised? What do they imply for restructuring and institutional reform in the public space? Can we somehow monitor the realisation (or the lack of realisation) of these values in societies?

The public space manifests itself at all levels: ranging from the local to the global. Here we are interested primarily in the international level (notably: in the United Nations or other interstatal structures, and in global networks of private sector actors and civil society organisations). Much of what will be said below also applies to the European level (be it the European Union or the Council of Europe) – this has not been elaborated.


3.1. Some preliminaries

First, I will discuss the reception thus far of declarations of global ethics. The UNMD has been endorsed by the UN General Assembly, and had engendered a set of more operational Millennium Development Goals adopted as objectives in developed countries’ policies for international cooperation. But UNMD apart, the official world largely refuses to formally endorse and recognize global ethics systems. The one that has come closest to some acceptance is the Earth Charter (the document that global civil society seems to feel most at ease with). Why is it so difficult to find a broader and more governmental and inter-governmental basis for this Charter? Dower (2004) has found several possible answers including: 1) incompatibility of its ethical tone with other perspectives: religious fundamentalism (and associated perspectives such as the ‘clash of civilizations’), relativist stances against universal values, nationalist or communitarian rejection of global responsibilities, free market libertarianism; 2) Rejection because of ‘moral weakness’ of states: they may feel that the Charter is too (morally) demanding. To this I suggest one further factor: 3) rejection by states on the basis of the political and economic costliness of its implications. An example of the latter would be the implied need for institutional reform.

Second, we need to be aware of features of the political and economic context in which these ethics have been put forward. In line with the analysis of Habermas (1981) one can see the world as ‘colonised’ by autonomous political and economic systems evolving according to their own inherent logic in a socially unresponsive way. In several of the declarations a critique is given of globalization and the economic forces steering it. Systemic features underlying a range of current global crises and dilemmas include:

– Virtually unaccountable economic agents operating on socially and politically «unembedded» markets beyond co-ordination and direction.

• an enhanced short-sightedness in political and economic systems, already denounced some 90 years ago by welfare economist Pigou as a ‘defective’ (and even ‘perverted’) ‘telescopic faculty’ leading to a shifting of social costs of private enterprise on to future generations; this is also clearly recognised in IC 1996;

• a prevailing culture and ideology supportive of market forces driven economic growth, rather than of rights based human development and responsibility for today’s weak, for future generations and for biodiversity.

Each of these dimensions needs to be addressed if the global issues are to be responded to, and most definitively if this is to be done while taking into account the interests of future generations and other species. Ways to do that in practice cannot be discussed here (see, however, Stiglitz, 2006 and Opschoor, 1994). They do require strong governance at regional (EU etcetera) and international levels – the three features mentioned above make that clear. Below we proceed in the areas of entitlement and ‘voice’ to be given to the stakeholders we are concerned with in this article.


3.2. Moving from Ethics to Institutional Reforms

Neither category of stakeholder can make itself heard in the public space directly: neither has a voice other than those of living human beings (and their organisations) speaking on behalf of these stakeholders. In the Habermasian ‘model’, the dominant economic and political systems (driven by market forces and a market logic, in a setting of economic globalisation) can hardly be expected to care for, and take into consideration our new stakeholders’ interests. Changing this requires the adoption of moral stances such as suggested by the ‘ethics’ discussed above, through individuals acting on behalf of future generations and/or other species in the public space, either through voluntary, bottom-up institutions and organisations (citizens’ initiatives, civil society organisations and the like), or though political action. To the extent that element in the economic system pose threats to our two categories of stakeholders, countervailing powers from either civil society or the political system might aim at curbing these threats – through regulation imposed on economic behaviour or economic agents, or – in theory, at least – by giving rights to these stakeholders that their ‘representatives’ might then defend on their behalf. In fact, what the global ethics discussed above do, is call on societies and/or their members to care, take responsibility and act in on behalf, or in defence of, these other stakeholders.

The materialization of these global ethics’ values materialize in society requires the spreading of new cultural/ideological systems, and the emergence of new «socially embedded» systems of governance (cf. the second point in 3.1). Of course, to the extent that these duties and responsibilities are not automatically recognised or accepted, communicative and educative action might have to be organised to attempt to make these global ethics become part of the dominant common sense and to facilitate democratic legitimacy.

In relation to all of that, what is needed is an adequate system of indicators to capture the world’s (and its constituent components) performance in relation to these values. We begin with the latter (3.2.1) to then explore to what extent these rights and duties are brought to bear on human beings active in today’s political arenas: at the level of policy and political strategy (III.2.2), and then that of institutions (3.2.3).


3.2.1. Values-related Performance Monitoring

What the world has, in this respects, is a system of Millennium Development Goals (MDGs) derived from values articulated in the Millennium Declaration and related statements from a variety of international conferences like the World Summit on Sustainable Development (Johannesburg, 2002). There are eight such MDGs; one (Goal 7) is on ensuring environmental security. It has 4 underlying targets: (i) the integration of the principles of sustainable development (SD) into country policies, (ii) a ‘significant’ reduction of biodiversity loss by 2010, (iii) halving the proportion of the population without access to safe drinking water and basic sanitation by 2015, (iv) improving the lives of at least 100 million slum dwellers by 2020. Of these, the first two relate directly to our concerns in this paper.

Related to the goal of integrating SD-principles into national policies, it is there that one should find targets and indicators capturing the interests of future generations. However, explicit reference is made only to the containment of emissions of greenhouse gases and ozone depleting substances. The principles themselves (the Rio-Principles, that is) do not feature in the MDG-system – yet, it it those that are most significant. Crucial ones amongst these 27 principles are: (a) a duty of states to ensure sustainable use of natural resources, (b) equity (including intergenerational equity) and the eradication of poverty, (c) the precautionary approach to human health, natural resources and ecosystems. From other sources we may take it that the implementation of these and other principles in national policies and legislation does occur, but in the MDGs this does not really feature.

Related to the target on biodiversity, monitoring takes place of marine areas, fish stocks, land conservation and deforestation, as well as of the number of species threatened with extinction. The indicators are relevant to our purpuse (factual performance with respect to it up till 2008 show sharp deteriorations).

Hence, operationalisation of values into development objectives and, subsequently into monitorable indicators has been far from adequate so far. They seem in better shape for biodiversity (with, however, deplorable outcomes according to the measurements) than for future generations – for which category there is no serious target outside emissions reductions for a number of gases.


3.2.2. Policy and strategic level

At the levels we are interested in here, the notion of sustainable development aims at covering the interests of one of these categories: future generations. This is clear from the definition of sustainable development: development that meets the needs of the present generation (including a fair sharing of the sources of well being), without jeopardising the capability of future generations to meet their needs and aspirations (WCED, 1987). This notion has been accepted globally from 1992 onward (the UN Conference on Environment and Development in Rio de Janeiro and its so-called «Rio Principles of Sustainable Development»). It now is enshrined as a global objective in various UN documents, and is accepted as an objective by many (probably most) countries. The Millennium Development Goals want to see the principles of sustainable development incorporated in national planning in all developing countries.

Biodiversity is addressed by the notion of sustainable development (see e.g. the report to the UNGA about it, and its chapter on biodiversity –WCED, 1987), but there, as we saw, the instrumental value(s) are explicitly subsumed as part of sustainable development, but the intrinsic values and related rights to existence and life support are not covered.

The Biodiversity Convention, signed at the 1992 UNCED, and ratified later, goes a little bit beyond that, in at least in its preamble recognising these intrinsic values, but in its operational parts it does not offer biodiversity much of a firewall beyond the instrumental or functional aspects. International CSOs have worked towards positions on biodiversity conservation, sustainable use of natural resources including biodiversity and the like, culminating in the 1981 World Conservation Strategy that has informed the 1982 UN World Charter for Nature and the subsequent BDC. Many ngos consider these documents to be far too anthropocentric to truly safeguard nature’s diversity.

The IC 1996 report asks for a new social contract, as a kind of umbrella for the policy strategies it stands for. In fact, it wants to empower people (the only recognized holders of sovereignty) and mobilize social forces towards developing a new social contract aimed at improving a sustainable and high quality of life (‘the central focus of policy’). At the heart of the contract would have to be a new commitment by all to strive for this sustainable and improved quality of life. The report is rather idealistic here. It does not really address the question of what to do when large groups of people, majorities or large minorities, refuse to accept this commitment or focus. This would even become worse if the two categories of stakeholders put central in this paper are also considered as requiring a place in a new Earth-wide social contract! What if society does not care for future generations, other life forms, or contemporary humans far away? What if people do not feel these responsibilities and/or reject the associated duties? Does the commitment then still stand? Or has it evaporated? Resorting to the common sense of people to articulate what they want for themselves (and maybe for their children and grandchildren) might be all right – assuming adequate information and communication. But as far as future generations in general and – even more so – other life forms are concerned, there is a representational gap in that those stakeholders cannot enter discourses about the social contract affecting them directly. The only way out is to ask today’s people to, based on an appeal to their civilisational responsibilities, adopt policies inspired by ethical charters such as the ones we have discussed and anchored in accepted and empowered institutional structures to make sure they will be there as firewalls when the viruses of self- centered and myopic human desires and priorities are turned loose on the other stakeholders. And that is the subject of the next paragraphs.

At the national levels Western countries have systems around the trias politica: legislative powers invested in parliaments, government bureaucracies to execute policies endorsed by (or initiated by) parliaments, and an independent judiciary for settling disputes between citizens and between citizens and the state. Often (not always) there are Constitutions articulating key elements of the social contract a country is based on and that can be used to verify the legitimacy of legislation. Human rights are mentioned there, and can also be protected by, e.g. the European Human Rights Court. At the international level there is no government; what is there is as association of states collectively forming the United Nations and its constituent parts (like Security Council and organisations such as FAO, WHO), and some other organisations created by states or governments, like the WTO, the World Bank and IMF, etc. But there are no ministry-like organisations and there are but very incomplete checks and balances of the trias politica kind. At the international level there also are organisations by and for the private sector and organised labour, and civil society organisations.

In addition to the above, states may agree to certain conventions to coordinate international activities in certain areas for which no generic UN-body exists (like the ones on biodiversity, and on climate change). There are quite many in the field of natural resources and the environment each one dealing with aspects or subdomains, such as trade in endangered species. Collectively they are referred to as MEAs: Multilateral Environmental Agreements. Their operations are normally co-ordinated through secretariats under the guidance of Conferences of the Parties to a particular agreement. As we saw, some of these MEAs refer to the International Court of Justice as an institution of last resort in dealing with conflicts between these parties. Such MEAs could be made for areas not covered by the existing one or existing one could be replaced by new, more adequate and effective ones. New institutions are very difficult to set up, though in the current international climate.

What does the existing system as described here have in store for our two categories of stakeholders?

– Future generations might be taken to in principle be entitled to treatment as human beings, but they have no explicit status in the UN Declaration of Human Rights. The closes we may come to that is the discussion about group rights in the context of human rights – such as the right to development, or the right to living in a healthy environment, but these have not had universal acceptance yet – or not as much as the individual human rights. And at any rate, future generations do not feature there explicitly.

– Other species have no set of rights comparable to human rights. One option might then be to consider giving them enforceable rights. For animals, this has been proposed by several globally recognised intellectuals, without much success so far (Martha Nussbaum, Peter Singer). The legal instruments provided by the CBD fall short of that – under CBD, countries who find that other countries give a wrong interpretation to CBD-articles could take them to the International Court of Justice. But that provides no security as states are committed only to do as much as is «possible»; moreover, only states can do this, not civil society organisations or other such ‘representatives’ of other species.

So, in terms of rights these stakeholders are not well taken care of. And this situation may prove to be difficult to change. An option apart from rights might be to find an international institution to look after the adherence to the responsibilities emanating from a global ethics. The UN has a (now dormant) Trusteeship Council assigned to it the task of supervising the administration of Trust Territories placed under the Trusteeship System. It was authorized to examine and discuss reports on the advancement of the peoples of Trust Territories and to examine petitions from and undertake periodic and other special missions to Trust Territories. There no longer are such territories. Possibly the Trusteeship Council could be re-animated (or a similar institution could be created) to be mandated to act specifically on behalf of the two categories of stakeholders put central here. A Trusteeship arrangement like this resembles that of an ombudsman, who is a trusted intermediary between an organization and the constituency thereof, to serve constituents interests. The UN as a proxy-custodian for future generations and other species could create a special office open to states and CSOs to submit requests on behalf of future generations and other species. A last option might be to enhance the powers of the existing formal structures (or create a new one with a broadened mandate) such as the UN Environmental Programme (UNEP) and the Commission on Sustainable Development (in ECOSOC – the highest dedicated body for issues to do with sustainability, but with a monitoring mandate only).


4. Conclusions

Ban Ki-Moon has said (June 2008, Kyoto): «Our duty and responsibility is to hand over this planet Earth of ours as a more hospitable and environmentally sustainable world to the next generation.» This idea should be extended to also cover societal responsibilities for non-human elements of biodiversity. There is a need for a transformation in the consciousness of individuals as a precondition for sustained reform in the public domain.

Several ethical systems have been articulated that deal with this, and they vary in their emphasis on social aspects or broader parts of the community of life; they also vary in terms of their focus on future generations. Together, they might inspire – and thus contribute to – a process of mobilisation of social (countervailing, to the extent necessary) power, towards a more community- oriented, sustainable and equitable future for all. Combining them, or elements from these several documents, a truly earth-oriented ethic might emerge that could be considered as a basis for societal policy making and strategy development towards the common human good (now and in future) and the interests of other life forms.

The emergence of global ethical thinking is not only important because of the increasingly global nature of the world’s problems and the causes thereof, but also to provide social support for changes in lifestyles, and particularly for changes in policies and institutions so as to bring about sustainable development.

On future generations, the rhetorics are clear but operationalisation fails so far. Our analysis discloses that their interests have not been satisfactorily translated into monitorable indicators. Their entitlements should be recognised, as the concept of ‘humanity’ encapsules all generations (past, present and future). Today’s international law allots too few rights to future generations. Nor are there dedicated, care-taking structures such as trusteeships or ombuds-organisations to address these concerns. This could be a point for serious international action – no doubt that would have to be triggered and inspired by internationally oriented non-governmental, civil society organisations operating in the domains of «nature» and «future».

On biodiversity, apart from CBD there is a need for progress in articulating and allocating «rights» (or equivalents of these) to other life forms, translated into duties or responsibilities of humankind to care. We also need structures to safeguard the interests of these other life forms, and they should be accessible from the lifeworlds of people living now – which again calls for actions from the grassroots.

An important step may be to work towards a globally acceptable, Earthwide ethics charter. Perhaps the existing Earth Charter, augmented with elements in the social domain as elaborated in Caring for the Future, could be such a contract.



Dower, N. (2004 ), «The Earth Charter as a Global Ethic», at        [ Links ]

Fortman, B. de Gaay and B. Klein Goldewijk (1998), God and the Goods: Global Economy in a Civilizational Perspective, WCC Publ., World Council of Churches, Geneva.

Fortman, B. de Gaay and B. Klein Goldewijk (1999), Where Needs Meet Rights: Economic, Social and Cultural Rights in a New Perspective, WCC Publ., World Council of Churches, Geneva.

Gilligan, C. (1982), In a Different Voice, Cambrige, Harvard University Press.

Goudzwaard, B. (1996), «Toward a European Economy of Care» in Bob Goudzwaard, Harry de Lange and Lars Ingelstam, Towards an Economy of Care and Compassion, ed by Alastair Hulbert, occasional paper nr 3 of the Ecumenical Association for Church and Society Brussels, EECS pp. 5-12

Goudzwaard B and Lange, H.M. (1995), Beyond poverty and affluence, Toward an economy of care, Eerdmans Grand Rapids & WCC Geneva.

Habermas, J. (1981), The Theory of Communicative Action II: Lifeworld and System: A Critique of Functionalist Reason, Beacon Press Boston.

IAC (Inter Action Council) (1997), A Universal Declaration of Human responsibilities. IAC.

IC (Independent Commission on Population and Quality of Life) 1996. Caring for the Future: making the next decades provide a life worth living, Oxford, Oxford Univ. Press.

Noddings, N (ed). (2005), Educating Citizens for Global Awareness, New York, Teachers College Press.

Opschoor J.B. (1994), «Market Forces as Causes of Environmental Degradation», in W. Zweers and J. J. Boersema (eds): Ecology, Technology and Culture: Essays in Environmental Philosophy, Cambridge, The White Horse Press, 175-197

Opschoor (2003a), «Economic, Social and Cultural Rights from an Economist’s Perspective », In K.Arts and P. Mihyo (eds) 2003, Responding to the Human Rights Deficit: Essays in Honour of Bas de Gaay Fortman, The Hague/New York, Kluwer Law International, 73-89.

Opschoor J.B. (2003b), «Sustainability: A Robust Bridge over Intertemporal Societal Divides?», in Van Seters, P., B. de Gaay Fortman and A. de Ruijter (eds) (2003): Globalization and its New Divides: Malcontents, Recipes and Reform, Amsterdam/West Lafayette, Dutch University Press/Purdue University Press, 79-100.

Opschoor (2007), «‘Wealth of Nations’ or ‘A common future’: religion-based responses to Unsustainability and Globalization», in Klein Goldewijk, B. (ed). Religion, Intertnational Relations and Development Cooperation, Wageningen Academic Publishers, 247-281.

Rockefeller S.C. (2007), Speech to the High-Level Dialoguie of the General Assembly on Religious and Intercultural Understanding and Cooperation for Peace – Informal Interactive Hearing with Civil Society, 4-5 October 2007. Earth Charter International, website.

Schrijver, N. (2006), Na ons de zondvloed: de positie van toekomstige generaties in het volkerenrecht, Boom Juridische Uitgeverij, Den Haag.

Stiglitz, J.E. (2006), Making Globalisation Work, New York, Allen Lane/Penguin.

UNDP (2000), Human Development Report 2000: Human Rights and Human Development – for freedom and solidarity, Oxford University Press.

Vilela, Mirian and Peter Blaze Corcoran (2005), «Building Consensus on Shared Values: History and Provenance of the Earth Charter, 17-22», in Earth Charter 2005: Towards a Sustainable World: The Earth Charter in Action, Amsterdam, Royal Institute of the Tropics (KIT).

WCED (World Commission on Environment and Development) (1987) Our Common Future, Oxford: Oxford University Press.

Witoelar, Erna (2005) «The Earth Charter and the United Nations Millennium Development Goals», 86-88, in Earth Charter 2005: Towards a Sustainable World: The Earth Charter in Action, Amsterdam: Royal Institute of the Tropics.



1 Two anonymous reviewers are thanked for their comments.

2 To put a name to it, some speak of a hegemonial ‘empire’; others have dubbed it the «Washington Consensus’ between the US, the IMF and the World Bank. It comes down to a project of economy-led development within institutional structures designed from a neo-liberal perspective. Some expect that his ‘consensus’ – that already started to give in to pressures based on social and ecological concerns, might be eroded further in the wake of the financial crisis and the global economic recession that followed it.

3 Human rights are not undisputed; often they are not accepted as universal, and, if they are actually laid down in law or manifesto, they cannot always be guaranteed or their relative status is ambiguous. Indeed: the proclaimed universality of HRs is a problem – whether one likes this or not. Some of the underlying values reflect notions that became manifest especially in parts of Western society after Humanism and the Enlightenment.

4 The paradox of care: there is an erosion of care (Gaay Fortman and Klein Goldewijk, 1996; see also IC, 1996) while average incomes are rising and care has a high income elasticity. That can be explained by lagging development of productivity in the care sectors, relative to the industrial ones. Salaries in the care sector cannot keep up with general salary level developments, or that will increasingly make care more expensive, so that demand will fall and/or public demand (in terms of budgets for care) will drop.

5 The CBD was preceded by the World Charter for Nature, adopted by the UNGA in 1982. That charter was based on an awareness that mankind is part of nature and that life depends on the uninterrupted functioning of natural systems, and that civilization is rooted in nature. Its general principles express respect for nature and its essential processes; the need to safeguard habitats of rare and endangered species, protect unique areas, ecosystems representatives, and species.


Texto recebido em Julho de 2009 e aceite para publicação em Dezembro de 2009.


*Prof. Dr J. (Hans) B. Opschoor, former rector and emeritus professor of the Economics of Sustainable Development, Institute of Social Studies, the Hague; emeritus professor of Environmental Economics, Free University, Amsterdam; member UN Committee for Development Policy; member Royal Netherlands Academy of Sciences.

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons