He explained that, too. He talked, thinking all the while that he was going to see her, and no living soul knew of it, and probably never would know. He had two lives: one, open, seen and known by all who cared to know, full of relative truth and of relative falsehood, exactly like the lives of his friends and acquaintances; and another life running its course in secret. And through some strange, perhaps accidental, conjunction of circumstances, everything that was essential, of interest and of value to him, everything in which he was sincere and did not deceive himself, everything that made the kernel of his life, was hidden from other people; and all that was false in him, the sheath in which he hid himself to conceal the truth -- such, for instance, as his work in the bank, his discussions at the club, his "lower race," his presence with his wife at anniversary festivities -- all that was open. And he judged of others by himself, not believing in what he saw, and always believing that every man had his real, most interesting life under the cover of secrecy and under the cover of night. All personal life rested on secrecy, and possibly it was partly on that account that civilised man was so nervously anxious that personal privacy should be respected.
... The Lady With The Little Dog, Anton Chekhov