Both St Teresa and Franz Kafka in The Interior Castle and The Castle explore the geography of the soul. The first is a sixteenth-century spiritual treatise cast in the form of an allegory, the second a modern piece of fiction presented as a novel. In each case, a failure to pursue these terms as definitions has led to a good deal of confused critical comment.

St Teresa begins: ‘While I was beseeching our Lord today that he would speak through me, since I could find nothing to say and had no idea how to begin to carry out the obligation laid upon me by obedience, a thought occurred to me which I will now set down, in order to have some foundation on which to build. I began to think of the soul as if it were a castle made of a single diamond or of a very clear crystal, in which there are many rooms, just as in Heaven there are many mansions. . . These words say exactly what the writer means them to; she is preparing the way to elaborate her image of the soul as a castle, just as St Augustine referred to Heaven as a city, or Bunyan to some of the landmarks on the way to the Celestial City as Doubting Castle and the Slough of Despond. Each example shows the language to be that of personal comparison—although, whereas the soul is a castle for St Teresa, for Bunyan Doubting Castle is the citadel of the Giant Despair.