Of all the means which wisdom acquires to ensure happiness throughout the whole of life, by far the most important is friendship (Epicurus, Principal Doctrines, 27)
It is assumed that wisdom strives for happiness. Without investigating the Epicurean sense of happiness, we may keep the idea that the wisdom is for something else than itself.
Though there are moral theories that can prove that wisdom is primarily for itself, only by disregarding the place of wisdom in humans we can overlook its direction to something else, too.
Epicurus considers that ‘something else’ has greater amplitude – ‘the whole of life’. The wisdom succumbs to the boundaries of the individual that exercises wisdom. Even if he surrounds all of his life completely with wisdom, the limits of his position in the world and the limits of the possibility of representing only wisdom in his life leaves the wisdom in a state of incompletion.
Whereas the incomplete things reach the completion as a natural integration of those missing parts that in fact belong to them, wisdom needs completion from something different.
In order to not loose its consistency, wisdom extends its property over the things that could complete it under the form of using them as means for reaching something else than itself. All that is outside of wisdom and wisdom accepts – as music, poetry, social life etc. – is primarily viewed as means. But only some of these external values become sheer instruments, while some come in the province of wisdom for shaping its form, not only for completing it.
Epicurus’ friendship is one of those formative means. Friendship undergoes the weakness of the wisdom in the limited wise man, since friendship expresses the humanity of such limit by bringing the human beings together.
And friendship modifies Epicurean philosophy: it is a philosophical reclusion into the innermost part of man by means of the recommended pleasure. The ideal of pleasure did not oppose to other moral ideals of Greek philosophy, many also inclined to privilege pleasure as a value of life, but, more than other philosophical theories, it was a recognition that wisdom is insufficient to man and to be completed by the man himself, adding to his weak individuality other individualities.