6. _Duties relating to friendship._--All the preceding duties are the same towards all men. There are others which concern more particularly certain men, those, for example, to whom we are attached either by congeniality of disposition or uniformity of occupation, or a common education, etc., those, namely, whom we call _friends_. The duties relating to friendship are: 1, to choose well one's friends; to choose the honest, and enlightened, in order to find in their society encouragement to right-doing. Nothing more dangerous than pleasure-friends or interested friends, united by vices and passions, instead of being united by wisdom and virtue; 2, the friends once chosen, the reciprocal duty is _fidelity_. They should treat each other with perfect _equality_ and with _confidence_. They owe each other _secrecy_ when they mutually entrust their dearest interests; they owe each other _self-devotion_ when they need each other's help. Finally, they owe to each other in a more strict and rigorous a sense, all they generally owe to other men, for the faults or crimes against humanity in general assume a still more odious character when against friends.
=21. Professional duties and civic duties.=--Such are the general duties of men in relation to each other, when simply viewed as men. But these duties become diversified and specialized according as we view man either in the light of the private functions he fills in society, which are his _professional_ duties, or in the light of the particular society of which he is a member, and which is called the _State_ or the country, and these are the _civic_ duties. (See chapters xii. and xiii.)
=22. Distinction between the duties of justice and the duties of charity.=--We have said above that all the social duties could be reduced to these two maxims: "Do not do unto others what you do not wish they should do to you. Do to others as you wish to be done by." These two maxims correspond with what is called: 1, the duties of _justice_; 2, the duties of _charity_.
The first consists in not doing wrong, or at least in repairing the wrong already done. Charity consists in doing good, or at least in giving to others what is not really their due. A celebrated writer[13] has made a very subtle and forcible distinction between these two virtues: