1. Personhood and Human Dignity as Foundation of Ethical Obligations and Fundamental Human Rights
Most of ethics rests on the insight into the sublime dignity of persons. Every human person, regardless of age, sex, race or other differences between different members of the species man, possesses a unique value, called "dignity," which lifts him or her up above all impersonal creatures. This human dignity is the source of a strict moral obligation to respect it during all phases of human life.
The ethical question of respecting human dignity, or better said, to respect any human person in virtue of the dignity of the person, is not at all restricted to the aspect of fundamental human rights. Both fundamental human rights and many moral obligations are founded on the same good, human life and its dignity, but the moral imperatives rooted in the dignity of persons go much farther and are in no way restricted to demands to respect the rights of persons. On the contrary, many spheres of moral and immoral acts have nothing to do with human rights; for example some of the most evil acts towards other persons, hatred and envy, are profoundly opposed to the moral requirements flowing from the value of the person as such but do not violate the rights of persons, as long as they do not attack the other person in actions or words.
But whereas the strict and universal moral obligation of the individual and of the state are more foundational and different from respecting any person’s “rights,” an important theme of ethics, to which we will now turn, concerns precisely the respect of human rights, especially the most fundamental ones.
Human dignity is an intrinsic and a very high value that raises a person up above all material entities, plants, and even animals. There are four quite fundamental senses or dimensions of human dignity. Each level or dimension of human dignity is the foundation of certain fundamental human rights. Some of these are grounded in the ontological fact of an inalienable human dignity that every human person possesses. To these basic human rights the right to life, the right not to be mutilated, sexually abused, or exposed to disease belong.
In the second dimension of human dignity, the “dignity of the consciously awakened person” (to which Pascal refers in his one-sided statement “all our dignity resides in thought”) many other fundamental human rights are grounded such as the right to free speech or the right to act according to one’s conscience.
Also in the third form of “acquired dignity,” especially “moral dignity,” many basic human rights are grounded such as the right to a good reputation, which the criminal certainly does not possess.
The same holds true for a fourth source of human dignity, the “bestowed human dignity,” in which again other rights are grounded, such as the dignity linked to the office of a judge which grounds the human right to independence of the judge.
2.The difference between rights of other persons (natural or positive legal claims) and moral obligations
Rights are distinct from moral imperatives chiefly for the following reasons:
They entail a certain claim on me on the part of the person who possesses a right, whereas on the fulfillment of my moral obligation as such no other person has a claim and a moral obligation is not “possessed” by any one as a right is.
They refer only to external actions of others and even in these only to the external side or part of these actions, not to the inner motives to which morality refers. Therefore vast spheres of moral life, inner responses and attitudes, as well as the inner moral intention underlying human acts, fall, with exception of the penal law, completely or at least largely outside the sphere of the law and my rights. I have no rights over another person’s submitting to his moral obligations while I do indeed have a right that he respects my rights.
Linked to this is the fact that rights, including natural or basic human rights, are enforceable and actionable. I can bring an action against someone before the court if he does not respect my right and the jurisdiction can force a person to respect my rights and punish transgressions. This is not possible with purely moral obligations and their fulfillment. Enforcing them would even be an absurd contradiction to their root in freedom.
Within rights we find many kinds. The most important ones of them are natural rights, which proceed from the nature and dignity of human persons or from certain human faculties and a priori structures of human acts. These we can call natural law in the strict sense (different from natural moral law) and fundamental human rights. These natural rights provide a natural foundation of human rights that no positive legislation is permitted to violate. Partly coinciding with them and partly differing from them are what Adolf Reinach calls a priori rights or laws, which I take to be the more general class of rights of which the natural human rights and fundamental human rights are the most substantial part. The main difference between them is that not all a priori laws are normative, quite unlike the natural human rights in the strict sense which are always normative and inalienable. Some of the a priori rights are only in a limited way “normative,” and instead of being quite “untouchable” by the state may be to some extent freely modified. For example, certain legal claims and obligations which proceed from the a priori essence of human acts, such as contracts or promises, may be suppressed by the positive law under certain circumstances.
Those rights which positive legislation gives us through legal enactments and positive law in general must be completely distinguished from these natural or pre-given rights that precede any positive legislation which, apart from enacting and in a sense creating new rights, has as its primary and most noble task to declare the fundamental human and natural rights, and to secure their enforceability by integrating them in the constitution, the preambles and catalogue of basic rights (Grundrechtskatalog) and by concretely applying them and their logical implications in more concrete laws.
Natural and authentic human rights are of central importance and utmost significance for human society and must be seen to be sharply distinguished from moral obligations even though they are closely related. (For example respect for human rights is also morally obligatory and part of the virtue of justice). The difference between moral obligations and human rights will become much more evident if we distinguish moral obligations from that sphere of natural rights or fundamental human rights that is closest to morality, namely “absolute rights,” such as the right to life, which could be simply identified with the moral obligation not to kill.
3. “Relative” and “absolute rights”
We should distinguish “relative” or better “relational rights” such as my right that a specific person who has made me a promise fulfill her promise or the rights of children in relation to their parents, and “absolute” rights such as the right to life which we have towards any human being and not only in relation to an individual. (Such “relative” or “relational rights” have to be distinguished from “conditional rights”).
My right to the promisor fulfilling the terms of a promise or of a contract he has entered with me constitutes a right of mine addressed to another person who has a legal obligation towards me to keep his promise; his obligation does not exist in relation to other persons nor does my right and justified claim exist towards others. My right to life is not of this kind; it is an absolute right, towards any other human being.
Now the “right to life” is obviously not an absolute right in the sense that a person would have an “absolute right to be given life through his parents,” or a “right to life in relation to God” (who would be forbidden or in whom it would be evil to take our lives or not to have given them, as it would be intrinsically evil and therefore impossible for God to punish us for personal crimes we have not committed as if we had committed them). Such absolute rights which even extend to our relation to God do exist, for example the right not to be judged unjustly or on the basis of lies and false accusations. The “right to life,” in contrast, is a right somebody receives upon being endowed with existence and which he possesses only with respect to other human persons, who have no right to destroy our life. They do not only lack a “moral right to kill us” but, if they do kill us, they not only commit a morally evil act but also violate our most foundational right to life. The “right to life” is a right of every innocent human being not to have his life taken by other human persons in a direct assault on it.
Calling this right to life an “absolute right” in the sense described does not mean the same absoluteness that the moral obligation not to kill an innocent person possesses. For the moral obligation does not have the same reference to an individual human person that a right has, regarding which another person has a claim towards or against me, which I would have the duty to respect. Morally speaking I am not obliged to a fellow human being but absolutely or in front of God. The moral obligation as such does not respond to another person’s natural right (just claim) to which the legal obligation refers. It does not have that earthly reference point in another human being that all rights, including the absolute right to life, have. We can see this difference better if we understand the following: I have no right that the other person fulfill her moral obligation not to kill me, an obligation that is quite independent of my rights as we can see when we consider that the same kind of moral ought also forbids the other person to hate me or to envy me, although in this case I do not have a right or just claim against her that she would violate through her hatred, whereas in the case of her violating my right to life I, or my legal representatives, if I actually die and am not only victim of attempted murder, do have such a claim against her. The obligation not to kill (just as “do not hate”, “do not envy and covet the goods of other persons”) is therefore an absolute one in another sense than the right to life.
It is not only addressed to everyone, but it also is not an obligation “towards me” or to any other human person, whereas the respect for my right to life has this character of respecting my right, and my claims and thus respecting something on which I have a claim. A moral obligation thus differs from a legal one based on human rights because any legal obligation exists towards a person and its fulfillment is owed to me (or to another individual or community).
 On the four dimensions and sources of human dignity, and the first and most foundational one of these, the ontological dignity of each human person, see Josef Seifert, The Philosophical Diseases of Medicine and Their Cure. Philosophy and Ethics of Medicine. Vol. 1: Foundations. Philosophy and Medicine, vol. 82 (New York: Springer, 2004), ch. 2.
 See on this Adolf Reinach, "The Apriori Foundations of the Civil Law," transl. by J. F. Crosby, Aletheia III (1983), pp. xxxiii-xxxv; 1-142. The original text is Adolf Reinach, "Die apriorischen Grundlagen des bürgerlichen Rechtes," in: Reinach, Adolf, Sämtliche Werke. Texkritische Ausgabe in zwei Bänden, Bd. I: Die Werke, Teil I: Kritische Neuausgabe (1905-1914), Teil II: Nachgelassene Texte (1906-1917); hrsg.v. Karl Schuhmann Barry Smith (München und Wien: Philosophia Verlag, 1989), pp. 141-278.
 I tried to show that the well-nigh complete freedom to modify them or to suppress their natural consequences of claims and obligations postulated by Reinach does not exist, even though are not in the same way “normative” as, let us say, the right to life. See Josef Seifert, "Is A. Reinach’s 'Apriorische Rechtslehre' more Important for Positive Law than Reinach Himself Thinks?", in Aletheia 3 (1983), pp. 197-230.
 The huge error of Hans Kelsen, Allgemeine Rechtslehre, was the belief that all rights and claims have their only reason and cause in the will, or the special acts of enacting positive laws whose nature Adolf Reinach beautifully analyzed in his main work, "Die apriorischen Grundlagen des bürgerlichen Rechtes," in: Reinach, Adolf, Sämtliche Werke. Texkritische Ausgabe in zwei Bänden, Bd. I: Die Werke, Teil I: Kritische Neuausgabe (1905-1914), Teil II: Nachgelassene Texte (1906-1917); hrsg.v. Karl Schuhmann Barry Smith (München und Wien: Philosophia Verlag, 1989), 141-278; "The Apriori Foundations of the Civil Law," transl. by J. F. Crosby, Aletheia III (1983), pp. xxxiii-xxxv; 1-142.
 See on this the very fine distinctions between conditional contents of an unconditional right and conditional rights as such. Adolf Reinach, "The Apriori Foundations of the Civil Law," cir.