Friendship, an apparently accessible and daily reality, is in fact a formidable challenge for thought, because it is something that one lives before actually understanding or defining it. And it is precisely when one seeks to determine its own requirements that it proves elusive, even disturbing, because it refuses to attach itself to some justification, because it is an insituable desire, perhaps even more so than love...
It is this concern that animates the essay by Emerson, published in 1841. It is part of a long tradition that passes through Aristotle and Montaigne, and which we will also find at Nietzsche, with his "star friendship". But Emerson shows in a particularly radical, lucid and direct way, how much contradictions and anxiety are charged with this seemingly simple and well-known feeling, pushed into its extreme consequences.