Cather's writing in "Paul's Case" is stylistically dense with imagery, metaphor, and motif. This heightened method of writing is emblematic of the dream state in which Paul lives most of his life. The prospect of mundanity is horrific to him, ultimately driving him to take his own life, so the words Cather uses to tell the story must mirror Paul's craving for elevation.
In keeping with this elevated style, Paul will often look to metaphor or symbolism as a means of explaining his own personal experiences, including justifying his decision to steal money and run away to New York:
Even when he was a little boy it was always there—behind him, or before, or on either side. There had always been the shadowed corner, the dark place into which he dared not look, but from which something seemed always to be watching him—and Paul had done things that were not pretty to watch, he knew. But now he had a curious sense of relief, as though he had at last thrown down the gauntlet to the thing in the corner.
In the above passage, Cather uses a more figurative style of writing to describe Paul's moral struggle, characterizing it as a dark "thing" in the corner with which he must contend, eventually "throwing down the gauntlet" and confronting his baser urges head on.