On arriving in Moscow by a morning train, Levin had put up at the house of his elder half-brother, Koznishev. After changing his clothes he went down to his brother’s study, intending to talk to him at once about the object of his visit, and to ask his advice; but his brother was not alone. With him there was a well-known professor of philosophy, who had come from Harkov expressly to clear up a difference that had arisen between them on a very important philosophical question. The professor was carrying on a hot crusade against materialists. Sergey Koznishev had been following this crusade with interest, and after reading the professor’s last article, he had written him a letter stating his objections. He accused the professor of making too great concessions to the materialists. And the professor had promptly appeared to argue the matter out.