Perhaps because it seems to be so universally experienced, the concept of friendship is difficult to pin down. The problem seems to lie in the fact that many things, which look like friendship, are not. Epictetus points this out in chapter 22 of The Discourses:
Well then, did you never see little dogs caressing and playing with one another, so that you might say there is nothing more friendly? but, that you may know what friendship is, throw a bit of flesh among them, and you will learn. Throw between yourself and your son a little estate, and you will know how soon he will wish to bury you and how soon you wish your son to die.
He goes on to explain:
For universally, be not deceived, every animal is attached to nothing so much as to its own interest. Whatever then appears to it an impediment to this interest, whether this be a brother, or a father, or a child, or beloved, or lover, it hates, spurns, curses: for its nature is to love nothing so much as its own interest; this is father, and brother and kinsman, and country, and God.
Epictetus is less cynical than he may appear, nor does he consider men merely to be animals. He does believe that there is something that sets men apart from the animals; something over which they have control and which can make for solid friendships. This is the will.
But examine, not what other men examine, if they are born of the same parents and brought up together, and under the same pedagogue; but examine this only, wherein they place their interest, whether in externals or in the will. If in externals, do not name them friends, no more than name them trustworthy or constant, or brave or free: do not name them even men, if you have any judgment... But if you hear that in truth these men think the good to be only there, where will is, and where there is a right use of appearances, no longer trouble yourself whether they are father or son, or brothers, or have associated a long time and are companions, but when you have ascertained this only, confidently declare that they are friends, as you declare that they are faithful, that they are just.
Externals can change and, with them, that which is based on these externals. However, the will is constant. Epictetus had taken the discussion of friendship out of mere description and placed the responsibility squarely on the one who would be a friend. Unfortunately, he did this at the expense of sterilizing friendship.
Socrates had tried to determine what friendship is in Plato's Lysis. When the dialogue gets to the main topic we find Socrates asking, "When one loves another, is the lover or the beloved the friend; or may either be the friend?" When an answer of either one is given, Socrates poses the situation of a man who loves without being loved in return. When it is agreed that this situation is possible, he sets up the first problem.
Then which is the friend of which? Is the lover the friend of the beloved, whether he be loved in return, or hated; or is the beloved the friend; or is there no friendship at all on either side, unless they both love one another?
It looks like some rather clever equivocation. After more of the same, Socrates reaches this conclusion:
If neither the beloved, nor the lover, nor the like, nor the unlike, nor the good, nor the congenial, nor any other of whom we spoke-for there were such a number of them that I cannot remember all-if none of these are friends, I know not what remains to be said.... O Menexenus and Lysis, how ridiculous that you two boys, and I, an old boy, who would fain be one of you, should imagine ourselves to be friends-this is what the by-standers will go away and say-and as yet we have not been able to discover what is a friend!
Perhaps Aristotle noticed the sophistry and did not agree that the conclusion was quite so hard to come by. He gives a more substantial argument in Book
VIII of his Nicomachaen Ethics.
Aristotle starts with the assumption that friendship must be mutual. He then differentiates three kinds of friendships based on the three kinds of love that can be mutual. The first two of these are based on what the lover can get out of the relationship. They are utility and pleasure. These cease as soon as the other party stops being useful or pleasurable. The useful changes more often. It can be descriptive, perhaps, of business acquaintances. These friends do not necessarily need to like each other. They are simply useful for the business at hand at that particular time.
The friendship of pleasure is perhaps more enduring. This friendship is dependent on emotion. For this reason, according to Aristotle, it seems to be common among young people. Yet, for this same reason, it is also subject to change, for the tastes of those who are maturing are likewise subject to change.
Aristotle saves perfect friendship for two men who are good. These men both love the good in the other and they love because they themselves are good. Because goodness is enduring, so are such friendships. According to Aristotle, these kinds of friendships do not come easily:
But it is natural that such friendships should be infrequent; for such men are rare. Further, such friendship requires time and familiarity; as the proverb says, men cannot know each other till they have 'eaten salt together'; nor can they admit each other to friendship or be friends till each has been found lovable and been trusted by each. Those who quickly show the marks of friendship to each other wish to be friends, but are not friends unless they both are lovable and know the fact; for a wish for friendship may arise quickly, but friendship does not.
Aristotle goes on to note that the two lesser kinds of friendship can resemble this perfect kind. Friendships based on the good are also both pleasant and useful. However, this kind of friendship is only possible when both men are good. Two bad men, or a bad and a good man may have friendships based on utility or pleasure. After reaching this conclusion, Aristotle moves toward a definition of friendship, which, in turn, leads to further qualifications:
Now it looks as if love were a feeling, friendship a state of character; for love may be felt just as much towards lifeless things, but mutual love involves choice and choice springs from a state of character; and men wish well to those whom they love, for their sake, not as a result of feeling but as a result of a state of character. And in loving a friend men love what is good for themselves; for the good man in becoming a friend becomes a good to his friend. Each, then, both loves what is good for himself, and makes an equal return in goodwill and in pleasantness; for friendship is said to be equality, and both of these are found most in the friendship of the good.
Equality is seen to be an important factor in friendship. Utility friendships last only as long as both parties are equally useful, for as soon as there is an inequity, the one receiving less for what he has put into it leaves. The same goes for friendships of pleasure. It would seem that Aristotle is wrong at this point. Since it is not possible to compare the subjective states of utility or pleasure between two individuals, then it would only be when one of them notices a change for the worse in the friendship that it would end. However, such a critique fails to take into account that Aristotle defines friendship as entailing a mutual love.
Almost. Aristotle then goes on to describe a different kind of friendship- that of unequals. Such is the case of father and son, elder and younger, husband and wife, master and servant. He is solves the apparent incongruity of this new kind like this:
In all friendships implying inequality the love also should be proportional, i.e. the better should be more loved than he loves, and so should the more useful, and similarly in each of the other cases; for when the love is in proportion to the merit of the parties, then in a sense arises equality, which is certainly held to be characteristic of friendship.
Such friendships, however, can only be unequal up to a point. If the distance becomes too great, the friendship cannnt be maintained. Aristotle goes on to write of the importance of friendship to such things as justice and the community. This gets a bit off the subject, so it is here that I must leave him. Yet, not before mentioning that, despite the praise that Aristotle gives to the friendship of the good, it still shares this quality with the other two: it lasts only as long as the lover is getting something out of the friendship (thus Epictetus' location of friendship in the will).
Thomas Aquinas, in his Summa Theologica I,II,26, addresses Aristotle's three fold division of friendship and his contention that "love is passion, while friendship is a habit." The particular question is Whether love is properly divided into love of friendship and love of concupiscence. Thomas answers by modifying Aristotle's distinction between love and friendship:
Love is not divided into friendship and concupiscence, but into love of friendship, and love of concupiscence. For a friend is, properly speaking, one to whom we wish good: while we are said to desire, what we wish for ourselves.
In saying this, Thomas has moved friendship into what is best for the beloved; not what the lover most desires for himself. As to the three-fold division of friendship, Thomas allows it with exceptions:
When friendship is based on usefulness or pleasure, a man does indeed wish his friend some good: and in this respect the character of friendship is preserved. But since he refers this good further to his own pleasure or use, the result is that friendship of the useful or pleasant, in so far as it is connected with love of concupiscence, loses the character to true friendship.
Friendships based on usefulness and pleasure may partake of the character of friendship; however, to the extent that they exist to fulfill the desires of the lover, they lose the character of friendship.
A further difference between Thomas and Aristotle is that Thomas allows for significant inequality in friendship, going even so far as to allow friendship with God. This friendship, while the inequality may not allow for it to be perfect according to Aristotle's definition, is, nevertheless, in the category of the good. We love God because he is wholly good. In loving us, God creates good in us.
Though Thomas did make significant improvements on Aristotle's concept of friendship, he did not go as far as Augustine. In IV, IV, 7 of his Confessions, Augustine speaks of a friend he once had:
But he was not then my friend, nor indeed ever became my friend, in the true sense of the term; for there is no true friendship save between those thou dost bind together and who cleave to thee by that love which is "shed abroad in our hearts through the Holy Spirit who is given to us." Still, it was a sweet friendship, being ripened by the zeal of common studies.
The importance of this passage for the progression of Christian thought on the matter is found in Augustine's distinction of true friendship. Although he will allow for a broader use of the term, apparently because of the constraints of language, he does not fall into the Greek mode of abstracting concepts, as though the friendships of believers and non-believers could be the same thing. Rather, he relies on scripture for his definition of friendship. True friendship is based on true love. True love is only possible as a gift of the Holy Spirit. Unbelievers cannot be true friends. They are, at best, left in Aristotelian categories.
Before dealing with the possibility of friendship between believers and non-believers, I would like to look further into a biblical concept and basis for Christian friendship. Such a friendship needs and has the endurance claimed by Epictetus of the will. However, it is not nearly as passionless nor does it rely on our own power. The basis of our being able to will friendship lies in our union with Christ and in the objective fellowship that we have with one another because of this union. We are called to practice friendship with believers because they, in fact, already are our friends. Nevertheless, while we remain in this world, this basis for friendship must find full expression in comparatively few instances. This is in part due to our lack of sanctification: sin still impedes our ability to love one another. It is in part due to our finitude: we cannot possibly love everyone with the intensity due someone who is united with Christ. We look forward to the day when neither of these qualifications are the case.
Aside from providing us with the basis for true friendship, scripture also shows us how it looks, both from narrative passages, such as the love between David and Jonathan, and from didactic passages from the life of Christ. The most striking feature, in distinction from Greek views, would seem to be the selflessness of true love and, consequently, of true friendship. John 3:16 is the most obvious example. Dealing more specifically with friendship is John 15:13, "Greater love has no one than this, that he lay down his life for his friends." These words, which are spoken by Jesus, are also fulfilled by him in his own death. It should not be thought, however, that friendship on the part of God leaves us without obligation. Jesus goes on, "You are my friends if you do what I command." But again, this obedience is not due merely to our own stoic will. As Thomas argues, God creates good in those he loves. We obey Christ, we are his friends, because he first loved and befriended us.
What then can be said about friendship between Christians and the world? True friendship may not be possible but may have to look like Aristotle's friendship of the good. Nevertheless, we can still practice true friendship toward them. It should be our passion that, just as God's friendship toward us created good in us, so too, through us, he may convert them into true friends. For this reason, true love toward them is necessary on our part. "Love your neighbor as yourself" really means it.