There is a definite congruence of thought about the characteristics of true friendship; familiarity, similarity, respect and trust are all qualities universally associated with friendship. While the ideas expressed about these and other aspects of friendship are largely the same from writer to writer, each writer brings to the discussion their own unique perspective. For this reason, it will be worthwhile to examine these qualities, of which I have enumerated eleven, in order to gain a deeper understanding of the nature of friendship.

1. Familiarity

One of the most essential elements of friendship is familiarity. Aristotle points this out when he draws a distinction between good will and affection by saying that "affection involves familiarity, whereas good will can arise on the spur of the moment." For Aristotle, while good will marks the start of friendship, it reveals that a relationship has not yet arrived at the maturity of affection. Cicero agrees with this view and draws upon some proverbial knowledge to make his point: "There is real truth in the familiar saying that people must eat many a peck of salt together if they are to know the full meaning of friendship." Ralph Waldo Emerson takes this idea one step further when he warns against friendships that are quickly constructed: "Our friendships hurry to short and poor conclusions, because we have made them a texture of wine and dreams, instead of the tough fibre of the human heart.... We snatch at the slowest fruit in the whole garden of God, which many summers and many winters must ripen." It is evident from these observations that two people must spend time getting to know each other before they can engage in a true friendship.

2. Choice

As two people become familiar with one another, they discover good and bad qualities in each other and on the basis of these qualities, they make a choice -- although perhaps not always consciously -- either to deepen their relationship with each other or to let it weaken. Choice is a key factor in the development of friendship; in the words of Aristotle, "mutual affection involves choice." When choice (as represented by good will) is eliminated from a relationship, it can no longer be truly called friendship, as Cicero points out: "Relatives may lose their goodwill, friends cannot, for once goodwill is lost, the friend is no longer a friend, but the relative is still a relative." This idea is made even more explicit by Montaigne, who speaks of choice as an exercise of free will:

Father and son may be of entirely different dispositions, and brothers also. He is my son, he is my kinsman, but he is an unsociable man, a knave, or a fool. And then, the more they are friendships which law and natural obligation impose on us, the less of our choice and free will there is in them. And our free will has no product more properly its own than affection and friendship.

Clearly, then, friendship involves an election or choice, and Montaigne intimates above that it is based on a similarity of disposition.

3. Shared situations and interests

Although Montaigne merely hints at this similarity between friends, Aristotle makes it explicit when he says that friendship involves an element of sharing: "Friendship is present to the extent that men share something in common... Friendship consists in community." On one level, Aristotle is speaking of a physical community. He makes numerous mentions of the fact that "nothing characterizes friends as much as living in each other's company." He also speaks of the sharing of common interests as a mark of friendship in his discussion of the master/slave relationship: "The part and the whole... have an identical interest; and the slave is a part of the master, in the sense of being a living but separate part of his body. There is thus a community of interest, and a relation of friendship, between master and slave..." Cicero takes the argument further when he states that "the one element indispensable to friendship [is] a complete agreement in aims, ambitions, and attitudes." From these arguments, it becomes evident that friendship does depend on a certain sharing and that the common element that brings men together can be a situation, a belief, a goal, or a disposition.