=Duties towards human life.=--Avoid homicide, acts of violence, and mutilation. Pascal and the _Provinciales_. =The right of self-defense.=--Right to oppose force to force. Limits of this right. =Problems.=--Four very grave problems are bound up in the question of self-defense: 1, the penalty of death; 2, political assassination; 3, the duel; 4, war. =The penalty of death.=--The penalty of death is the right of self-defense exercised by society: it is just so far as it is efficacious. =Political assassination.=--Murder is always a crime, under whatever pretext it may conceal itself. =The duel.=--The duel is at the same time a _homicide_ and a _suicide_; it is falsely considered justice, since it appeals to chance and skill. =War.=--War is the only mode of self-defense existing among nations; it is desirable for the sake of humanity that it may some day disappear; but humanity cannot now exact this sacrifice of the country. =23. Division of social duties.=--According to the foregoing distinctions, we will first divide duties into _duties of justice_ and _duties of charity_. Let us begin by expounding the duties of justice. These duties may be summed up in a general manner in _the respect for the person of others_, and for all that is necessary for the preservation and development of that person. Hence four kinds of duties: 1. Towards the life of other men. 2. Towards their liberty. 3. Towards their honor. 4. Towards their property. Besides these duties, purely negative, which consist only in doing others no harm, there are also the duties of justice, which may be called _positive_; and which consist not only in not injuring others, but also in granting each what he has a right to. This is called _distributive_ or _remunerative_ justice, and is the duty of all those who have others under them, and who are commissioned to distribute rewards, titles, or functions. =24. Duties towards the life of men.=--We have seen above that self-preservation is the duty of every one, and that one should not attempt one's own life, nor mutilate one's self, nor injure one's health. Now, all these obligations which we have towards ourselves, we have equally towards others; for that which each owes to himself, he owes it to his quality, as _man_, to his quality as a free and reasonable being, a _moral person_. It is, as Kant says, humanity itself that each one must respect in his own person; and it is also humanity which each must respect in others. We should not do to others what we do not wish that they should do to us, or what we should not wish to do to ourselves. Now, no one wishes others to attempt his life; no one should wish to attempt it himself. For the same reason he should not wish to attempt the life of others.