"necessary and accidental"

"Taking possession of this new abode, I put on my thinking cap.  I reasoned more or less as follows: Civilization is a thing both necessary and accidental; like the lining of a nest, it is a shelter from the world, a tiny counterworld that the large world silently tolerates, with the toleration of indifference, because in it there is no answer to the questions of good and evil, beauty and ugliness, laws and customs. Language, the creation of civilization, is like the framework of the nest; it binds all the bits of lining and units them into the shape that is deemed necessary by the occupants of the nest. Language is an appeal to the joint identity of the nesting beings, their common denominator, their constant of similarity and therefore its influence must end immediately beyond the edge of that subtle structure."

-- Stanislaw Lem, His Master's Voice