It is a fundamental principle of most moral theories that all human beings have a right to life. The existence of a right implies obligations or duties of third parties towards right-holder. One has a right AGAINST other people. The fact that one possesses a certain right - prescribes to others certain obligatory behaviours and proscribes certain acts or omissions. This Janus-like nature of rights and duties as two sides of same ethical coin - creates great confusion. People often and easily confuse rights and their attendant duties or obligations with morally decent, or even with morally permissible. What one MUST do as a result of another's right - should never be confused with one SHOULD or OUGHT to do morally (in absence of a right).

The right to life has eight distinct strains:

IA. The right to be brought to life

IB. The right to be born

IC. The right to have one's life maintained

ID. The right not to be killed

IE. The right to have one's life saved

IF. The right to save one's life (erroneously limited to right to self-defence)

IG. The Right to terminate one's life

IH. The right to have one's life terminated

IA. The Right to be Brought to Life

Only living people have rights. There is a debate whether an egg is a living person - but there can be no doubt that it exists. Its rights - whatever they are - derive from fact that it exists and that it has potential to develop life. The right to be brought to life (the right to become or to be) pertains to a yet non-alive entity and, therefore, is null and void. Had this right existed, it would have implied an obligation or duty to give life to unborn and not yet conceived. No such duty or obligation exist.

IB. The Right to be Born

The right to be born crystallizes at moment of voluntary and intentional fertilization. If a woman knowingly engages in sexual intercourse for explicit and express purpose of having a child - then resulting fertilized egg has a right to mature and be born. Furthermore, born child has all rights a child has against his parents: food, shelter, emotional nourishment, education, and so on.

It is debatable whether such rights of fetus and, later, of child, exist if fertilization was either involuntary (rape) or unintentional ("accidental" pregnancies). It would seem that fetus has a right to be kept alive outside mother's womb, if possible. But it is not clear whether it has a right to go on using mother's body, or resources, or to burden her in any way in order to sustain its own life (see IC below).

IC. The Right to have One's Life Maintained

There is no such right as there is no corresponding moral obligation or duty to save a life. This "right" is a demonstration of aforementioned muddle between morally commendable, desirable and decent ("ought", "should") and morally obligatory, result of other people's rights ("must").

In some countries, obligation to save life is legally codified. But while law of land may create a LEGAL right and corresponding LEGAL obligations - it does not always or necessarily create a moral or an ethical right and corresponding moral duties and obligations.

IF. The Right to Save One's Own Life

The right to self-defence is a subset of more general and all-pervasive right to save one's own life. One has right to take certain actions or avoid taking certain actions in order to save his or her own life.

It is generally accepted that one has right to kill a pursuer who knowingly and intentionally intends to take one's life. It is debatable, though, whether one has right to kill an innocent person who unknowingly and unintentionally threatens to take one's life.

IG. The Right to Terminate One's Life

See "The Murder of Oneself".

IH. The Right to Have One's Life Terminated

The right to euthanasia, to have one's life terminated at will, is restricted by numerous social, ethical, and legal rules, principles, and considerations. In a nutshell - in many countries in West one is thought to has a right to have one's life terminated with help of third parties if one is going to die shortly anyway and if one is going to be tormented and humiliated by great and debilitating agony for rest of one's remaining life if not helped to die. Of course, for one's wish to be helped to die to be accommodated, one has to be in sound mind and to will one's death knowingly, intentionally, and forcefully.

II. Issues in Calculus of Rights

IIA. The Hierarchy of Rights

All human cultures have hierarchies of rights. These hierarchies reflect cultural mores and lores and there cannot, therefore, be a universal, or eternal hierarchy.

In Western moral systems, Right to Life supersedes all other rights (including right to one's body, to comfort, to avoidance of pain, to property, etc.).

Yet, this hierarchical arrangement does not help us to resolve cases in which there is a clash of EQUAL rights (for instance, conflicting rights to life of two people). One way to decide among equally potent claims is randomly (by flipping a coin, or casting dice). Alternatively, we could add and subtract rights in a somewhat macabre arithmetic. If a mother's life is endangered by continued existence of a fetus and assuming both of them have a right to life we can decide to kill fetus by adding to mother's right to life her right to her own body and thus outweighing fetus' right to life.

IIB. The Difference between Killing and Letting Die

There is an assumed difference between killing (taking life) and letting die (not saving a life). This is supported by IE above. While there is a right not to be killed - there is no right to have one's own life saved. Thus, while there is an obligation not to kill - there is no obligation to save a life.

IIC. Killing Innocent

Often continued existence of an innocent person (IP) threatens to take life of a victim (V). By "innocent" we mean "not guilty" - not responsible for killing V, not intending to kill V, and not knowing that V will be killed due to IP's actions or continued existence.

It is simple to decide to kill IP to save V if IP is going to die anyway shortly, and remaining life of V, if saved, will be much longer than remaining life of IP, if not killed. All other variants require a calculus of hierarchically weighted rights. (See "Abortion and Sanctity of Human Life" by Baruch A. Brody).

One form of calculus is utilitarian theory. It calls for maximization of utility (life, happiness, pleasure). In other words, life, happiness, or pleasure of many outweigh life, happiness, or pleasure of few. It is morally permissible to kill IP if lives of two or more people will be saved as a result and there is no other way to save their lives. Despite strong philosophical objections to some of premises of utilitarian theory - I agree with its practical prescriptions.

In this context - dilemma of killing innocent - one can also call upon right to self defence. Does V have a right to kill IP regardless of any moral calculus of rights? Probably not. One is rarely justified in taking another's life to save one's own. But such behaviour cannot be condemned. Here we have flip side of confusion - understandable and perhaps inevitable behaviour (self defence) is mistaken for a MORAL RIGHT. That most V's would kill IP and that we would all sympathize with V and understand its behaviour does not mean that V had a RIGHT to kill IP. V may have had a right to kill IP - but this right is not automatic, nor is it all-encompassing.

III. Abortion and Social Contract