My Year With Proust - Day 339

   "But are you sure that M. de Charlus has had all those mistresses?" I asked, not, of course, with the diabolical intention of revealing to Robert the secret that I had discovered, but irritated, nevertheless, at hearing him maintain an erroneous theory with such smug assurance.  He merely shrugged his shoulders in response to what he took for ingenuousness on my part. "Not that I blame him in the least, I consider that he's perfectly right." And he proceeded to outline to me a theory of conduct that would have horrified him at Balbec (where he was not content with denouncing seducers, death seeming to him the only punishment adequate to their crime). Then, however, he had still been in love and jealous. Now he even went so far as to sing the praises of houses of assignation. "They're the only places where you can find a shoe to fit you, sheathe your weapon, as we say in the Army." He no longer felt for places of that sort the disgust that had inflamed him at Balbec when I made an allusion to them, and hearing what he now said, I told him that Bloch had introduced me to one, but Robert replied that the one which Bloch frequented must be "pretty vile, a poor man's paradise! - It all depends, though: where was it?" I remained vague, for I had just remembered that it was there that Rachel whom Robert had so passionately loved used to give herself for a louis. "Anyhow, I can take you to some far better ones, full of stunning women." 

Marcel Proust, Cities of the Plains, pp. 718-719

Out of the blue Marcel's sadness about the impending death of Swann, and the concomitant period of reflection, is interrupted by the unexpected arrival of his old friend Robert.  And, as is the case with young men, a young's fancy turns to love, even love tainted by a negotiated fee (which a cynic would propose is all love).  Robert starts discussing brothels and the deeper reflections are a thing of the past.