A great deal of effort in Sodom and Gomorrah is devoted to the ways in which language hides the world rather than revealing it. The second half of the book returns Marcel to Balbec and surrounds, where the once-mysterious place names from Swann's Way are transformed for Marcel into symbols for people he knows, stations along the local railway where the little train stops long enough for people in the carriages to get out and chat or have a drink with residents of the towns. Marcel has also learned several possible etymologies of many of the local place names (traditional etymologies from a local vicar's book on the subject, and possibly-more-exact etymologies from Brichot, a scholar in one of the social circles Marcel joins). The names found on maps or train timetables are vestiges of names that once signified the agrarian use of lands or the ownership of property, of places where one could fish or cut trees for lumber. Many of the place names are connected (directly or indirectly) with names of France's great families, depending on who is giving the etymologies or genealogies (there is no clear consensus on any of this). This business with the historical ("true, original") meaning of names, which mean one thing in common use but also carry hidden--sometimes quite different--meanings of their own, is a metaphor for the whole of language, for the whole of human discourse. Charlus speaks in a kind of doublespeak code--revealing his sexuality while attempting to disguise it--in conversations with people who are quite sure about Charlus' tastes but speak to him as if they are unaware of it, all the while making private jokes to each other about Charlus, right in front of him. Morel--after whom Charlus longs with a passion so powerful it could destroy him, a passion that makes him abase himself before Morel even in front of witnesses--says whatever is convenient at any given moment in order to maintain his childish pride and his control over Charlus. Everyone says one thing and means something else. Everyone is in an agony of desire, pretending otherwise when they can and humiliating themselves when they cannot, all the while smiling and leaving visiting cards and shaking hands on the train station platform as they are all carried from hotel to hotel, party to party, during a long summer vacation that must, of course, come to an end. We lie to one another and ourselves without realizing we are lying, without knowing that we lie to push back our despair, we stuff ourselves with lies to fill holes in ourselves we don't even know we have. Marcel, aware that he does not want Albertine, must have her because he knows she does not want him. Everyone becomes Swann or Odette, though by now we must realize how miserable Odette must've been, with Swann relentlessly pursuing her, misunderstanding her lies though she was certain he knew what she was really saying. How dumb we all are.
The place names/family names theme also reveals to us how the mysteries of life (once where Marcel would look at a map of France he'd imagine all sorts of romances behind the exotic names of towns he'd never seen, or when he would see the names of the nobility in the papers or overhear them in the conversation of adults he would imagine the glittering and brilliant lives connected to those names) become mundane once encountered and examined (the exotic locales of Brittany transform into a mere list of places where one can shake hands with an acquaintance one can very well live without, and the famous names reveal themselves as belonging to wealthy but shallow folks who are no better than those people to whom they refuse to be introduced). Which is not to say that this new perception of reality is true; it is merely another thing we tell ourselves, merely another layer of language obscuring whatever reality actually is. Language is what we tell ourselves, not a map of the world.