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COMMENTARY

The human actor in ecological economics: Philosophicalapproach and research perspectives

Christian Becker⁎

University of Heidelberg, Alfred-Weber-Institute for Economics, Bergheimer Str. 20, 69115 Heidelberg, Germany

A R T I C L E I N F O

⁎ Tel.: +49 6221 54 8017; fax: +49 6221 54 802E-mail addr ess: cbecke r@uni-hd.de.URL: www.eco-eco .uni-hd.de.

0921-8009/$ - see front matter © 2006 Elsevidoi:10.1016/ j.ecolecon.2005. 12.016

A B S T R A C T

Article history:Received 10 August 2004Received in revised form9 December 2005Accepted 21 December 2005Available online 28 February 2006

This paper contributes to the discussion about an adequate understanding of the humanactor in ecological economics. It provides a philosophical approach by defining threefundamental relations of the human being: its relation (i) with itself, (ii) the community and(iii) nature. I reflect on previous discussions within ecological economics and argue thatespecially the relevance of the third sphere has not fully been recognized, yet. For thisreason, I present the concept of homo ecologicus, which describes the relation of the humanbeing with nature as an inherent principle of human excellence and is not based on mereself-interest or the striving for biological survival. Homo ecologicus is characterized by(a) sympathy with and respect for nature, (b) an orientation of its own creativity upon thecreativity found in nature, and (c) a relation with nature, which is especially based onpersonal experience and encounter with it. I draw conclusions of the relevance of thisconcept for ecological economics and finally, I suggest a sensible integration of a variety ofconcepts of the human actor in order to explore the different relationships andcharacteristics of human existence, which are all important for the subject area and theaims of ecological economics.

© 2006 Elsevier B.V. All rights reserved.

Keywords:Ecological economicsHomo biologicusHomo ecologicusHomo economicusHomo politicusHomo sustinens

1. Introduction

Ecological economics examines the relationship betweennature and the economic system in the broadest sense(Costanza, 1989; Proops, 1989; Faber et al., 1996: 1, Edwards-Jones et al., 2000: 3). It has already been recognized that thisambitious research task requires a reflection on the under-standing and the modeling of the human actor in ecologicaleconomics. Contributions to this discussion have been madeby Faber et al. (1997), Söderbaum (1999), Siebenhüner (2000),Nyborg (2000), Jager/Janssen (2000), Gintis (2000) and Faber etal. (2002). This paper provides a systematic philosophical

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er B.V. All rights reserved

analysis of this issue. Existing contributions will be character-ized and attention drawn to aspects not previously examined.

For an encompassing analysis of the understanding of thehuman actor in ecological economics, I refer to three funda-mental levels of the human relationship: (i) The relation of thehuman being with itself, (ii) the relation of the human beingwith other humans and (iii) the relation of the human beingwith nature. The relevance of these three spheres forecological economics will be discussed in Sections 2–4. I willargue that, while the first and second sphere have beenaddressed by previous contributions, the importance of thethird sphere – the relationship between humans and nature –

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has not adequately been recognized and analyzed, yet. Thisaspect will be discussed in detail and an understanding of thehuman being as homo ecologicus will be presented, throughwhich this third sphere can be sensibly addressed (Section 5).Conclusions from this analysis for the understanding of thehuman actor in ecological economics are drawn in Section 6.

In discussing the three spheres mentioned, I will not onlyregard their relevance in a positive analysis of the relationshipbetween nature and the economic system, but also take intoaccount that ecological economics has a normative dimensioninasmuch as it addresses the question of how a sustainableeconomy can be implemented (Costanza, 1991) or, moregenerally, how a long-lasting compatibility of nature and theeconomic system can be achieved. Thus, within my analysis Itake into account both epistemological as well as ethicalaspects.

Every concept of the human being I refer to in this paper isan abstraction. It is a construct which reduces the complexityand variety of human beings to a few characteristics. Asensible construct of the human being or the human behaviorshould, in general, fulfill two conditions. (1) It should be asuitable and fruitful tool for approaching and analyzing therespective subject matter and questions of research, particu-larly for generating insights, explanations and predictions. Inthis respect, it is a heuristic concept. (2) It should be plausible inthe sense that the characteristics ascribed are phenomenolog-ically evident.1 Therefore, the underlying assumption of thispaper is that there are such characteristics which can plausiblybe ascribed to the human being, and there is more than one.2

2. The sphere of human self-interest: homoeconomicus

In mainstream economic theory, the human actor usuallyappears as homo economicus: a selfish, rational, utility maxi-mizer.3 Modern economic models refer to human beings asself-related beings characterized by a specific rationality4 andby a concentration on their own self-interests. Many con-tributions have criticized the homo economicus as aninadequate concept for ecological economics. In empiricalstudies, for example, references have been made to experi-mental results which show that humans do not always actrationally or in pursuit of self-interest (Jager and Janssen, 2000:

1 This does not mean that such characteristics are necessaryattributes of every human being, which can be proved empirically.2 I do not intend to enter a philosophical discussion about the

“real essence” of the human being. I rather make suggestions forconcepts of the human being which are fruitful and plausible forecological economics. I do not wish to answer the question ofwhat the human being really is, but rather of how we can depict itfor reaching further scientific progress in ecological economics.3 See, e.g. Mueller (1989: 2). For a detailed critical analysis of the

understanding of the human being in modern economics seeManstetten (2000).4 Here, I refer to the traditional understanding of rationality in

standard economic theory, which is a very specific and narrowone. Rationality here means the ability to bring one's ownpreferences in a consistent order, and to decide and act on thisbasis in an optimal way, i.e. to maximize one's own utility oroutcome under the given conditions.

307; Siebenhüner, 2000: 17f). However, the crucial question isnot whether homo economicus can be proved or disproved inevery empirical situation. It is a construct whichmay certainlybe adequate and fruitful for the analysis of many purelyeconomic situations, and, in general, the characteristics it isbased on can be regarded as phenomenologically plausible.Rather, the crucial question is, whether this construct issuitable for the research task of ecological economics or, if thisnot the case, what other characterizations and alternativeconcepts of the human being could be more so.

The construct of homo economicus implies specific andlimited perspectives on the relation of the human being withfuture generations or the relation of the human being withnature. Both relations cannot be fully captured and, therefore,there cannot be any encompassing considerations on thecentral tasks of ecological economics – the quest for sustain-ability and the quest for the relation between the economyand nature – on the basis of the homo economicus concept.

On the basis of this concept, we can neither attribute asystematic interest in future generations to the presentgeneration nor explain it. This would, however, be crucial forfurther considerations on the concept of sustainability (Faberet al., 2002: 324f). Of course, homo economicus can have apreference for the well-being of future generations, but this is,if anything, incidental. It may be the case. It is not, however, asystematically inherent attribute of the concept of homoeconomicus. In fact, there is a potential conflict between theunfolding of the self-interest of homo economicus andsustainability; since it is hardly possible to imagine asustainable development which does not require any restric-tion on today's generation and its self-interests. Thus, itseems questionable whether homo economicus provides asufficient basis for seeking encompassing concepts of sus-tainable development.

A similar problem occurs if we seek a long-lastingcompatibility of nature and the economic system. The homoeconomicus approach also implies a specific and narrowrelation between humans and nature. Nature turns out as anobject of human self-interest, a bundle of goods serving thepurpose of satisfying human preferences (Baumgärtner et al.,in press). This construct ultimately implies some oppositionbetween human beings and nature. Its heuristic potential forthe understanding of the relation between the economy andnature and the search for a long-lasting compatibility of bothis thus limited, too.

Within ecological economics, one therefore has to con-sider whether there are other sensible constructs of thehuman being and its motivation of action more suited to thetask of this discipline. Here, the history of philosophicalthought can provide important insights. It has always beenrecognized that the human being has other dimensionsbeyond its self-relation, and that solely with reference to thelatter, many aspects of human existence and actions cannotfully be understood. In fact, it has been claimed that it isessentially the relation to others which makes human beingshuman. Aristotle (1984: 1253a) regarded the human being aszoon politicon which means that only in the relation to thecommunity and the active participation in the polis canhumans realize the perfection of their being. Rousseau ([1755]1995: 70f) states that there are two moments which

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essentially characterize the human being: self-love andsympathy with other beings. In his ethical considerations,David Hume ([1772]1998: 168) ascribes a principle of “[…]benevolence, distinct from self-love […]” to human nature.Adam Smith denoted not only selfishness (see e.g. Smith,[1776] 2000: I.ii.2 and IV.ii.6) but also sympathy as a specificcharacteristic of the human being (Smith, [1759] 2000: I.i.1.1).In recent philosophy, for example Spaemann (2000) refers tothe relation of the human being with other beings as aconstitutional moment of its reason.

The concentration on self-relation as a characteristic of thehuman being in modern economics is a reduction which maybe justified by the subject area of economics. The subject areaand the research task of ecological economics, however, differfundamentally frommainstream economics, and thus requirea different underlying assumption about the human being.One should therefore overcome the narrow and specificconcept of homo economicus and rethink traditional conceptsin philosophy, which describe the systematic relation to otherbeings as an important trait of the human being. In thefollowing, I will distinguish two central possibilities of such arelation: the relation to other humans (Section 3), which hasalready been discussed in ecological economics, and therelation to other beings, or nature in general (Section 4), whichhas not really been discussed, yet.

3. The relation to others: community andfuture generations

The philosophical tradition suggests that human beings arenot only self-related, but that they are, independent of theirmere self-interest, systematically related to the community.This insight is backed up by results of modern biology,psychology and experimental economics (Jager and Janssen,2000; Siebenhüner, 2000), as well as by phenomenologicalevidence. It has been taken up within ecological economicswith the concept of homo politicus (Nyborg, 2000; Faber et al.,2002) or the Political Economic Person (Söderbaum, 1999), andalso with the concept of homo sustinens by Siebenhüner (2000).

Siebenhüner (2000: 20) refers to insights of evolutionarybiology and psychology and denotes “cooperation andcommunication” as important human characteristics. Gintis(2000: 311) refers to experimental results which show thathuman actors in strategic, economic situations behave“cooperative[ly] and prosocial[ly]”. He states that “[…]economic actors are not self-regarding, but rather in manycircumstances are strong reciprocators who come to strate-gic interactions with a propensity to cooperate, respond tocooperative behaviour by maintaining or increasing cooper-ation, and respond to free-riders by retaliating against the‘offenders’, even at personal cost […]”. While these argu-ments are based on results of empirical science, Faber et al.(2002), like Söderbaum (1999), provide philosophical reasonsfor an inherent interest of human beings in the community.The homo politicus developed by Faber et al. (2002: 328) isbased on ethical considerations and essentially character-ized by its “striving for political justice”. It recognizes thisstriving as an essential trait of its existence as a beingcapable of reason.

A systematic relation of human beings with the communi-ty, which is not based on individual self-interest, may thus bereasoned. However, is this sufficient for ecological economics?If we aspire sustainability, we ask not only for intra-genera-tional justice but also for inter-generational justice, and hence,seek reasons for an ethical relation of human beings to futuregenerations. This is a different ethical dimension. Obviously,one cannot conclude a necessary human trait of responsibilityfor future generations from observed prosocial or cooperativeaspects of human behavior. It is not even clear if an ethicalrelation defined among current actors applies in the samemanner for people living in different times and, in particular, ifit can be extended to future generations. Faber et al. (2002: 330),however, hold that their concept of homo politicus providesreason for sustainability, because in this concept, the strivingfor a just order of the community is an essential characteristicof human existence and, therefore, the long-lasting protectionof this community becomes an independent value in itself.

However, it is an overly narrow notion of sustainability toconcentrate only on the relation human beings have withcurrently living and future generations. The subject area ofecological economics is much broader: if we are interested in ageneral analysis of the relationship between nature and theeconomic system, we should also ask how the relationbetween humans and nature, relevant for this issue, can bedescribed and sensibly captured.

4. The relationship between humans andnature

How is human life connected with nature? Are there specificcharacteristics of human beings which relate them to natureand which are not guided by their self-interest (as homoeconomicus) or their interest in the community? Are thereimportant consequences for the understanding of the humanbeing within ecological economics? These questions haverarely been discussed.

One obvious level of the relationship between humansand nature is the biological level. Human beings have muchin common with other animals. They must ensure theirsurvival as biological beings and, on this level, they arenecessarily dependent on nature: on food, water, air, etc.This dimension of human existence has sometimes beencalled homo biologicus (Manstetten et al., 1998: 134). Ashomines biologici, humans are directly related to natureand dependent on it. This circumstance does not becomeobvious in modern economics, because it deals with relativescarcity, i.e. assumes that there is always a possibility tosubstitute goods or production factors (Robbins, 1932: 13ff).This particularly applies for natural goods or productionfactors, which, in principle, are regarded as goods or factorslike all others, substitutable with other natural or artificialgoods or capital (Baumgärtner et al., in press).

It is the achievement of ecological economics to recognizeand express the limitations of this view of nature in light of themodern environmental crisis: “[…] nature really does imposean inescapable general scarcity” (Daly, 1980: 8). Ecologicaleconomics questions whether an endless substitution ofimportant natural goods and services is possible. In this

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respect, nature is regarded as an absolute limitation forhuman (economic) actions5 and, implicitly, the human beingis understood as a homo biologicus. This understandingemanates particularly from the importance placed on thefact that there is a limitation of substitution of natural goodswhich are absolutely necessary for human survival.

Addressing this elementary relationship between humansand nature is important because it points out the inescapablebiological dependency of the human life on nature,which doesnot become apparent in modern economics or whenever thehuman being is regarded exclusively as homo economicus. Itis, however, not a sufficient understanding of the human actorfor ecological economics. In this view, the human being is, inessence, regarded as a biological being like all others in nature.Its exceptional role in nature is not considered and it seemssomewhat reduced. We do not only understand ourselves asmere biological beings but also as moral beings able to takeresponsibility for our actions. Andwe are not only interested inourmere survival, but also in a good life andhumanexcellence.

These aspects are of great importance for ecologicaleconomics. With regard to its subject area – the relationshipbetween nature and economic action – one should, forexample, consider to what extent humans have a responsibil-ity for nature. Or, more generally, whether there is an inherentand systematic relation of thehumanbeingwith nature beyondthe dimensions of homo economicus and homo biologicus,which can serve as a basis for a long-lasting compatibilitybetween the economic system and nature. What role doesnature play for the humanbeing and the striving for a good life,beyond its mere function of guaranteeing the basis forsurvival? Iwill discuss thesequestions in the following section.

5. Homo ecologicus

Several thinkers in the history of philosophy have describedthe relationship between humans and nature beyond themere biological sphere and the sphere of narrow self-interest.In the following, I particularly refer to romantic naturalphilosophy6 and to recent discussions on virtue ethics7 in

5 Indeed, the entire argumentation based on the second law ofthermodynamics ultimately serves to support this statement.Following the initial works of Georgescu-Roegen (1971) and Daly(1980),many contributions in ecological economics argued that theeconomic process is dependent on and limited by this natural law.6 The Romantics in Europe and America developed an impor-

tant and influential natural philosophy, which in particularreflects on the meaning of the modern economy and of moderneconomic thought for the human–nature relationship (Becker,2003). I especially refer to the German romantic Novalis (1772–1801), the English poet William Wordsworth (1770–1850) and theAmerican transcendentalist Henry David Thoreau (1817–1862).7 Virtue ethics is an important school of thought in current

moral philosophy (besides deontology and utilitarianism). Itaddresses issues like “the motives and character of moral agents”,“moral education”, “a deep concept of happiness, the role of theemotions in our moral life, and the question of what sort ofperson I should be, and of how we should live” (Hursthouse, 1999:2f). It has its origins in the philosophy of Plato and Aristotle. Forgeneral considerations on virtue ethics see, e.g. Crisp and Slote(1997) or Hursthouse (1999).

environmental philosophy (see, e.g. Sandler and Cafaro 2005).Following these schools of thought, I develop the concept ofhomo ecologicus as an example of a concept which describes therelationship between the human being and nature beyond(economic) self-interest and biological survival. It depicts adimension of the human being which supplements thedimensions of homo economicus and homo biologicus andprovides a new philosophical basis of research for ecologicaleconomics.

I define homo ecologicus through three characteristics:(i) its relation with nature is based on sympathy andrespect, (ii) it orientates its creativity upon nature and (iii)its relationship with nature is especially based on personalexperience and encounters with it (see also Becker, 2003:265ff). These characteristics are thought of as inherentmoments of a good life and human excellence. That meansthat in this way an ethical relationship with nature isdefined. Thus, these characteristics are not arbitraryindividual preferences, but inherent necessary momentsof the concept. I will explain the three characteristics indetail.

Ad (i) It is a specific characteristic of the human beingthat it has the ability to have sympathy with otherbeings, human and non-human (as stated already byRousseau, [1755]1995: 70f). It can recognize otherbeings as beings who differ from itself and havetheir own and independent existence. It canrecognize other beings as other selves in their ownright and encounter them with respect and sympa-thy. The recognition of and respect for the otherself means a limitation of one's own self: theexistence and the right of the other is acknowl-edged. However, within the concept of homoecologicus, this limitation is not understood as ahindrance for the development of the human being,but rather as an inherent condition for humanexcellence. In this concept, it is an essentialcharacteristic of the human being and its good lifeto recognize the existence of an other self in itsown right and to encounter it with respect andsympathy. For such an encounter some differencesand some similarities are necessary. The other selfhas to be recognized as a You, which has somethingin common and something different (or evenstrange) with Me. This is the basis for an encounterand a dialogue which lead to both understanding ofand respect for the opposite. The Romantics, espe-cially Novalis, regarded nature in this way — as aYou (Becker and Manstetten, 2004). The Romanticshold that the possibility of sympathy with naturalbeings and the recognition of them as selves in theirown right (as a You) is a special human character-istic which relates human beings in a specific waywith nature. For them, human excellence essentiallyrequires such an encounter with nature (Becker,2003).

Ad (ii) Creativity can be seen as a common basis whichhuman beings share with nature and which allowsa real encounter with it as a You. ‘Creativity’ has

9 This aspect was pointed out very clearly by Thoreau (2002:201). Thoreau developed an important philosophy of nature inwhich the personal empirical encounter with nature plays acentral role. Although he was very critical of the economic systemof his time – regarding this form of economy as destroying thetrue relationship between humans and nature – he thought ofpractical solutions which could overcome the division of modern(economic) man and nature: “I think that each town should havea park, or rather a primitive forest, of five hundred or a thousandacres, either in one body or several, where a stick should never be

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been described as a characteristic of homo susti-nens, too (Siebenhüner, 2000: 20). I will add someconsiderations on the meaning of creativity for therelationship between humans and nature (or econ-omy and nature). Humans are not only rationalbeings as the concept of the homo economicussuggests, but also creative beings who can bringforth inventions, arts, ideas, etc. The economicprocess is also not only characterized by rationaldecision-making, but by an immense creativity — astestified by endless new inventions and products.Nature, however, expresses creativity as well. In theevolutionary process, it brings forth endless newforms and beings. While rationality, in general, isascribed to humans and separates humans fromnature, creativity seems to be an essential charac-teristic of humans and nature. The Romantics,however, suggest that human creativity is notabsolute, like the creativity of God, but relative,which means that it requires orientation. Forthem, this orientation can only be found in nature(see, e.g. Wordsworth, [1805] 1979: XII 370ff).8

Human creativity is seen as the highest form ofthe creativity found in nature and has to acknowl-edge the duty to orientate upon nature's creativity,to reflect and celebrate it. Thus, finally, the creativ-ity of human beings has to be the perfection ofnature's creativity.This view is not as obscure for ecological economicsas it might appear at first. Bionics or IndustrialEcology, for example, implicitly have such an under-standing of the relationship between humans andnature (see, e.g. Isenmann, 2003). Industrial Ecologyregards natural processes – which are acknowledgedas almost perfect recycling processes – as models forindustrial processes. However, the idea of IndustrialEcology, to orientate human economic processesupon natural processes, remains on a mere technicallevel. It has not been underpinned with an adequateunderstanding of the human being, which cansensibly be thought of as orientated upon nature.The idea of economics as a creative process andcreativity as an essential characteristic of the humanbeing (as homo ecologicus), which connects it and itseconomic actions with nature, could be a fruitfulunderstanding of the (economic) human actor; notonly for industrial ecology, but for ecological eco-nomics in general.

Ad (iii) The relationship between humans and nature is notsimply a theoretical one. It has a practical dimensionwhich can only be recognized by personal experi-ence. The concept of homo ecologicus includes thisaspect of empirical subjective experience and knowl-edge, which the personal individual encounter with

8 For further considerations on the meaning of Wordsworthianthought for the history and foundations of ecological economicssee Becker et al. (2005).

nature provides.9 Practical personal environmentalexperience clearly differs from theoretical knowledgeabout nature. It is crucial for the two characteristicsof homo ecologicus discussed above. These have tobe cultivated by practical encounters with nature,and their meaning for a well-lived life and humanexcellence has to be experienced. Furthermore,practical environmental knowledge is of generalimportance for the analysis and solution of environ-mental problems (Faber et al., 1996: 231ff). Theseaspects have also been covered to some extent byconcepts which regard ecological economics as atransdisciplinary or a post-normal science (Funto-wicz and Ravetz, 1994; Müller, 2003). Here, aninterconnection of science with social groups andtheir experience, practical knowledge and aims isrequired (Thompson Klein et al., 2001). In thisrespect, also the theme of personal learning byencounter with nature becomes important for eco-logical economics. Environmental education whichhas been recognized as an important issue withinecological economics (Clark, 1991; Zucchetto, 1991; LeMaitre et al., 1997: 116f), should, therefore, have apractical dimension: it should not merely concen-trate on imparting abstract (scientific) knowledgeand norms but also include personal encounter withand experience of nature.10

6. Conclusions

The human being features various dimensions and character-istics. An abstraction, which maintains some of these in amore or less simplified concept, can be carried out in a numberof plausible ways. Some have been sketched in this paper. Aconcept, which always means an abstraction and reduction,gains its legitimacy through the insights and knowledge it cangenerate in respect to a certain subject area. Thus, the homoeconomicus might be useful for many purely economicquestions but it is, in general, not adequate for ecologicaleconomics and its subject area— the relationship between theeconomic system and nature. Further dimensions and char-acteristics need to be considered.

10 For a general discussion on environmental education seeSchneider et al. (1992). For the aspect of personal experience seeespecially (ibid. 56ff).

cut for fuel, nor for the navy, nor to make wagons, but stand anddecay for higher uses — a common possession forever, forinstruction and recreation.” (Thoreau, 2002: 201; see also Becker,2003: 200ff).

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I have based my considerations on three fundamentalrelations of the human being: its relation with itself, itsrelation with the community and its relation with nature.Due to the subject area of ecological economics, I hold thatthe third relation is of great importance for this discipline.Thus, I have offered the concept of homo ecologicus whichconcentrates on specific characteristics relating the humanbeing to nature beyond mere (economic) self-interest or thestriving for biological survival. In this concept the relationwith nature is essential for human excellence. This justifiesa systematically intrinsic striving of homo ecologicus torespect and protect nature. Furthermore, I interpret creativ-ity as a unifying characteristic of humans and nature andalso regard the economic process as an expression of humancreativity. This particularly enables the justification ofconsiderations in industrial ecology that economic struc-tures should be orientated upon natural ones; considerationswhich should also be included and discussed further inecological economics in general. Finally, for ethical as wellas epistemological reasons, personal encounter with andexperience of nature is defined as one essential character-istic of homo ecologicus.

However, for encompassing research into the relationshipbetween economic action and nature, ecological economicsshould not concentrate merely on one specific understandingof the human actor. The quest for a sustainable and ecologicaleconomy has many dimensions and all concepts of thehuman being discussed in this paper can illuminate differentaspects of the entire picture. Homo biologicus reveals thedependency of humans on nature. Homo politicus and homosustinens clarify different aspects and preconditions of inter-and intra-generational justice. Homo economicus is also ofimportance, especially for short term solutions which makeuse of economic incentives. Homo ecologicus, finally, denotesaspects and preconditions for discussing a long-lastingharmony between the economic system and nature. However,since the different existing concepts are not in tune whicheach other, obviously there are tensions and contradictionsbetween them. Therefore, further research on this issueshould seek an integrated concept of the human actor,which captures all the characteristics and relations of thehuman being, relevant for ecological economics, in a sensibleand consistent way.11 The ambitious task of ecologicaleconomics does not allow a narrow reduction and modeling

11 I do not refer to tensions between different interests of humanbeings in reality or to the question, if and how they can be solved(see Söderbaum, 1999: 164). I rather suggest the possibility of asensible integrated and consistent intellectual construct of thehuman actor for ecological economics. It is not reasonable to referto ourselves as beings, which are ultimately inconsistent, nor canthis be a fruitful basis for the research task of ecologicaleconomics. The challenge is to develop a consistent construct ofthe human being, integrating the variety of human dimensionsand avoiding a simple reduction to one dimension. In my point ofview, one cannot conclude fundamental tensions in reality fromtensions between the different concepts, or vice versa. Tensionsbetween the existing concepts of the human being rather resultmainly from a too exclusive or too far extended use or under-standing of a single construct and may be eliminated by adequatelimitation and hierarchic ordering.

of the human being but requires an awareness of a variety ofcharacteristics of the human being and of the three funda-mental relations mentioned by which it can be defined.

Acknowledgements

I thank Maximilian Mihm and Annika Sterrenberg for fruitfuldiscussion and advice on style and language. I am further-more grateful to Stefan Baumgärtner, Malte Faber, JensKohne, Mi-Yong Lee-Peuker, Reiner Manstetten, ThomasPetersen, Maik Schneider and three anonymous referees forhelpful comments. Finally, I thank the Deutsche Forschungsge-meinschaft (DFG) and the Volkswagen Foundation for financialsupport.

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