the final enclosing isolation of obsession — "This, the final enclosing isolation of…"

The endgame stated as pure enclosure: the father will no longer leave the den — eventually not even for the bathroom — sealed alone with the object of his compulsion until he dies in the chair before it. Marathe supplies the diagnosis in the abstract ("the final enclosing isolation of obsession"), and the phrase reads as the disease's terminal geometry: every appetite of this kind narrows, at the last, to one man alone in one room with the only thing left that he wants.