Do You Exist, Mr. Lem?

Throughout his career, Stanisław Lem revisits the problem of “persistency of identity,” asking whether two instantiations of the same thing can ever be determined to be entirely the same or independent from each other. In this article, I consider several instances in which Lem sets up fictional or analytic thought experiments to probe the persistence of identity and our strategies for testing it, with particular attention to his novel Solaris and his early radio play “Do You Exist, Mr. Johns?” Reading these texts and Lem's commentaries, we find that Lem uses such thought experiments to demonstrate the inadequacy of the experiments themselves. Time and again, we find that for Lem the inscrutability to oneself is a key feature of subjectivity, but it is also the feature of subjectivity that is least legible to an outside observer and least likely to support external confirmation.