Albert Camus's The Stranger is considered timeless and universal because it is an existential text which deals with the intrinsic nature of life, the insignificance of the individual, life's absurdity, and accompanying alienation--all of which are themes prevalent in many literary works.
Much like Hemingway's stoic protagonists, Mersault tries to squeeze from life what he can because only nothingness waits at the end of life; it is in the living of life that one carves out one's existence and meaning. When others place a value upon death, which is nothingness, and when a certain behavior is prescribed, Mersault, as an individual, feels his freedom of choice is threatened. As a man he is alienated when he does not conform to particular customs and beliefs. At his trial, for instance, he becomes disassociated with what transpires as his lawyer argues for him according to a set formula of defense:
His tactic had been not to file any motions so as not to antagonize the jury. He explained to me that verdicts weren't set aside just like that, for nothing. That seemed obvious and I accepted his logic. Looking at it objectively, it made perfect sense. Otherwise, there would be too much pointless paperwork. "Anyway," he said, "we can always appeal....
The way in which the lawyer so casually discusses the possible outcomes for Mersault connotes small value of an individual life, an existential fact that confronts all men.