One of the main achievements of modern societies is the universal recognition of human dignity: all human beings possess a unique and unconditional value; they are entitled to basic rights just by being part of Humanity. No other qualifications of age, sex, ethnic or religious origins are needed. Today, at the juridical and political level, the «inherent dignity» of human beings is unanimously recognized. According to Dworkin, anyone who professes to take rights seriously must accept «the vague but powerful idea of human dignity».
Even if our era is characterized by the decline of universal foundations and criteria, paradoxically, no other time has presented such an existential sense of universality. «The human Phenomenon appears for the first time as a Phenomenon which exists and covers with its universality the diversity of conditions and particular situations». Beyond all socio-cultural and philosophical differences between peoples, there seems to be the need and the expectation of human dignity among all civilizations. The requirement has always been that «something is due to the human being by the only fact that he or she is human».
2. The theoretical difficulties of human dignity
A second paradox is related to the eminent place classically attributed to human person in the cosmos, that supposes a sharp separation between humans and the rest of nature. Human beings possess an unconditional value, they are end-in-themselves, while animals and plants are just means to serve human needs. This idea is clear in the Judeo-Christian belief, according to which the whole creation is at the service of human persons, the only beings on earth that are «image and likeness» of God. It may be noted, however, that the anthropocentrism of the religious viewpoint is still relative: humans are regarded as subordinated to God and not having an absolute power over nature, which also reflects, though to a lower degree, God himself. It was not until the Rationalist philosophers that this anthropocentrism was exaggerated. If before, human beings had been simple administrators of nature with limited authority, they were now in possession of tyrannical powers. At the same time, the disenchanted nature no longer reflects a cosmic order, which inspires respect; it is just matter (res extensa), submitted to the unlimited power of humans.
3. Conclusion: towards a more concrete approach to human reality?
The preceding analysis showed some of the difficulties raised by the concept of human dignity in the context of genetic advances. Within this framework, the greatest dilemma can be summarized in a few words: how can we explain the notion of dignity and even more, how can we justify the notion itself, avoiding at the same time, as far as possible, the recourse to (too strong) metaphysical arguments?
If beginning from the «top», that is, from metaphysical concepts, in order to explain the idea of dignity is «forbidden» in our postmodern time, perhaps we should begin from the «bottom», that is, from concrete relations to other individuals as particular persons with distinctive needs. That means that the way out of the labyrinth in which we are placed is probably a new effort to rediscover the human person in its concreteness and only then deducing general rules. Because how will we be able to preserve the human person, if we do not know it, if it does not exist, if it is nothing more than a concept?
Some modern philosophers have developed concrete approaches to human reality which can perhaps be helpful in order to better explain the idea of dignity. Emmanuel Levinas is one of them. According to him, the contemplation of the human face is the most significant way to discover the incommensurability of each individual. The relation with the face is «a relation with the other absolutely other, which I cannot contain, with the other in this sense infinite»; the face of the other resists our power to assimilate him or her into mere knowledge. The face of the other silently remembers us the command: «you shall not commit murder». For him, ethics emerges primarily on the concrete level of the contact from person to person. The responsibility for the other as a singular being, with singular needs and concerns, establishes «me» in a unique relationship, as irreplaceably responsible for the «other». The Levinasian approach does not find the moral «ought» inscribed within the laws of the cosmos. Instead each individual case of moral conflict produces the moral «ought» itself. In other words, responsibility for the other is born primarily in the face-to-face situation and not in purely theoretical knowledge. It is worth stressing that this approach does not commit any «naturalistic fallacy», because the starting point is not an «is» but already an «ought».
If this kind of argumentation is valid, then we have to focus our moral attention on the other in his or her concreteness, as a particular person with distinctive needs. From this basis, we have to develop a more realistic explanation of human dignity. Perhaps a more experiential approach, which takes concrete human beings with their hopes and their sufferings, as the starting point of its reflection, could help us to rediscover the infinity which is present in every individual and to find fair solutions to the new bioethical dilemmas.
 See Herbert Spiegelberg, «Human Dignity: A Challenge to Contemporary Philosophy», in Human Dignity. This Century and the Next, ed. R. Gotesky and E. Laszlo, New York, Gordon and Breach, 1970, p. 62.
 Dan Egonsson, Dimensions of Dignity. The Moral Importance of Being Human, Dordrecht, Kluwer, 1999, p. 34.
 See, for example, Ulfrid Neumann, «Die Tyrannei der Würde», Archiv für Recht und Sozialphilosophie, 1998, 2, p. 153; Dieter Birnbacher, «Ambiguities in the concept of Menschenwürde», in Sanctity of Life and Human Dignity, ed. K. Bayertz, Dordrecht, Kluwer, 1996, p. 107; Martin Hailer and Dietrich Ritschl, «The general notion of human dignity and the specific arguments in medical ethics», in Sanctity of Life and Human Dignity, p. 91; Claudia Wiesemann, «Medizinethik und Menschenwürde. Paradox und Dekonstruktion», in : Die Würde des Menschen, edited by H. Kössler, Erlangen, Universitätsbund Erlangen-Nürnberg, 1998, p. 104.
 The Oxford Encyclopedic English Dictionary, New York, Oxford University Press, 1996, p. 398.
 Universal Declaration of Human Rights, United Nations (1948), Preamble.
 Ronald Dworkin, Taking Rights Seriously, Cambridge, Harvard University Press, 1977, p. 198.
 Paul Ricoeur, «Pour l’être humain du seul fait qu’il est humain», in Les enjeux des droits de l’homme, Paris, Larousse, 1988, p. 236.
 «Concern for the interests of the subject must always prevail over the interests of science and society» (art. 5, Helsinki Declaration of the World Medical Association).
 See Geneva Convention Relative to the Protection of Civilian Persons in Time of War, 1949; International Covenant on Economic, Social and Cultural Rights, 1966; International Covenant on Civil and Political Rights, 1966; Convention on the Elimination of All Form of Discrimination against Women, 1979; Convention Against Torture and other Cruel, Inhuman or Degrading Treatment or Punishment, 1984; American Declaration of the Rights and Duties of Man, 1948; American Convention on Human Rights, 1969, etc. See also Béatrice Maurer, Le principe de respect de la dignité humaine et la Convention européenne des droits de l'homme, Paris, La documentation française, 1999.
 See a detailed commentary on this article by Ernst Benda: «Die Würde des Menschen ist unantastbar», in Beiträge zur Rechtsanthropologie, ed. Ernst-Joachim Lampe, Stuttgart, Steiner Verlag, 1985, p. 23.
 See Constitution of Belgium, art. 23; Constitution of Switzerland, art. 119 (concerning biotechnological interventions on human beings and nature); Constitution of Ireland, Preamble; Czech Republic Constitution, Preamble; Constitution of Spain, art. 10; Constitution of Sweden, art. 2; Constitution of Finland, art. 1; Constitution of Greece, art. 7.2; Constitution of Poland, Preamble, art. 30; Constitution of Lithuania, art. 21; Constitution of Slovenia, art. 34; Constitution of Russia, art. 21; Constitution of South Africa, Section 7.1 and Section 10; Constitution of Mexico, art. 3.1, 25; Constitution of Israel, art. 1; Constitution of Brazil, art. 1; etc. See a selection of legal texts which mention dignity explicitly, in Dignity, Ethics and Law, ed. J. Knox and M. Broberg, Copenhagen, Centre for Ethics and Law, 1999.
 See Robert Spaemann, «Über den Begriff der Menschenwürde», in Menschenrechte und Menschenwürde, ed. E.-W. Böckenförde and R. Spaemann, Stuttgart: Klett-Cotta, 1987, p. 297.
 Dieter Birnbacher, «Ambiguities in the concept of Menschenwürde», p. 110. At the same time, the author recognizes that the principle of human dignity enounced in art. 1 of the German Constitution «is clearly more than a mere summing up the human rights of the articles 1 to 19» (p. 113).
 Philipp Balzer, Klaus Rippe, Peter Schaber, Menschenwürde vs. Würde der Kreatur, Freiburg/München: Alber, 1998, p. 28.
 Martin Hailer and Dietrich Ritschl, «The general notion of human dignity and the specific arguments in medical ethics», p. 93.
 In France, the jurisprudence has considered that the practice consisting in the throwing of dwarfs (lancement de nains) is contrary to human dignity because it reduces the person to the status of a mere object. Therefore, it can be forbidden by local authorities (see Conseil d’État, October 27, 1995, Revue française de droit administratif, 1995, p. 878).
 See art. 1: «All human beings are born free and equal in dignity and rights».
 See Universal Declaration of Human Rights, art. 6: «Everyone has the right to recognition everywhere as a person before the law». In an analogous approach, it has been said that «the protection of dignity concerns the protection of the natural conditions without which man cannot be Subject» (Ludger Honnefelder, «Person und Menschenwürde», in Philosophische Propädeutik, ed. L. Honnefelder and G. Krieger, Paderborn, Ferdinand Schöningh, 1996, p. 261).
 «Whereas disregard and contempt for human rights have resulted in barbarous acts which have outraged the conscience of mankind... » (Universal Declaration of Human Rights, 1948, Preamble).
 Universal Declaration of Human Rights, Preamble.
 Ronald Dworkin, Life's Dominion. An Argument About Abortion, Euthanasia and Individual Freedom, New York, Vintage, 1994, p. 236.
 Ronald Dworkin, ibid.
 See Kurt Bayertz, «Human Dignity: Philosophical Origin and Scientific Erosion of an Idea», in Sanctity of Life and Human Dignity, ed. K. Bayertz, Dordrecht, Kluwer, 1996, p. 88.
 Grundlegung zur Metaphysik der Sitten, Berlin: Akademie-Ausgabe, vol. IV, 1911, p. 428.
 Ibid., 434. The contrast between persons and things is indeed one of the best ways to approach the notion of human dignity. It is precisely the blurring of this distinction that gives rise to the so-called reification of person. See Roberto Andorno, La distinction juridique entre les personnes et les choses à l’épreuve des procréations artificielles, Paris, LGDJ, 1996; La bioéthique et la dignité de la personne, Paris, PUF, 1997; in Spanish: Bioética y dignidad de la persona, Madrid, Tecnos, 1998.
 Grundlegung zur Metaphysik der Sitten, p. 436.
 See Peter Kemp, «Four Ethical Principles in Biolaw», paper at the 2nd International Conference on Bioethics and Biolaw, Copenhagen, 3-6 June 1998, p. 8. The interpretation of Kantian texts is not unanimous. For other specialists, even adopting a Kantian position we cannot deduce from the principle of autonomy that the weakest human beings are not persons (See Jan P. Beckmann, «Patientenverfügungen: Autonomie und Selbstbestimmung vor dem Hintergrund eines im Wandel begriffenen Arzt-Patient-Verhältnisses», Zeitschrift für Medizinische Ethik, 44, 1998, p. 146).
 H. T. Engelhardt, The Foundations of Bioethics, New York, Oxford University Press, 1996.
 Gen., 1, 26.
 This is why this perspective does not exclude the idea of duties towards nature, which is called to join man in praising God (See Psalm 148).
 «I have a clear and distinct idea of myself inasmuch as I am only a thinking and unextended thing, and as, on the other, I possess a distinct idea of body, inasmuch as it is only an extended and unthinking thing, it is certain that this I, that is to say, my soul by which I am what I am, is entirely and absolutely distinct from my body, and can exist without it» (Meditationes de prima philosophia, VIth meditation).
 Thomas De Koninck, De la dignité humaine, Paris, PUF, 1995, p. 16. See also Xavier Dijon and Christianne Hennau-Hublet, «Les droits de l'homme, corps et âme: la déchirure bioéthique», in Dignité humaine et hiérarchie des valeurs. Les limites irréductibles, ed. S. Marcus Helmons, Louvain, Academia-Bruylant, 1999, p. 33.
 Kurt Bayertz, «Human Dignity: Philosophical Origin and Scientific Erosion of an Idea», p. 88. See also from the same author: «Die Idee der Menschenwürde: Probleme und Paradoxien», Archiv für Recht und Sozialphilosophie, 1995, p. 465.
 Kurt Bayertz, «Human Dignity: Philosophical Origin and Scientific Erosion of an Idea», loc. cit.
 In this sense, it is sometimes invoked as an argument against human dignity the fact that human DNA and DNA of chimpanzees are identical in more than 99%.
 Peter Singer, Animal Liberation, New York, Avon, 1977, p. 7.
 Dieter Birnbacher, «Ambiguities in the concept of Menschenwürde», p. 114.
 Let us not forget that some of the most prominent defenders of animal rights do attack the principle of unconditional respect of human life, and justify such practices as euthanasia and infanticide. See Peter Singer and Helga Kuhse, Should the Baby Live ? The Problem of Handicapped Infants, Oxford, University Press, 1985; Peter Singer, Rethinking Life and Death: The Collapse of Our Traditional Ethics, New York, Oxford University Press, 1995.
 Totality and Infinity, The Hague, Nijhoff, 1969, p. 197.
 Ibid., p. 199.
 See this kind of approach with reference to the concept of human rights in: Roberto Andorno, «Les droits de l'homme sont-ils universels?», Etat de droit, droits fondamentaux et diversité culturelle, Paris, L'Harmattan, 1999, p. 199.