The title of the third chapter of this text reveals the symbol and the theme:"My Fool-Saint." This chapter describes the curious fascination that Mrs. Dempster exerts on Dunstable Ramsay, who is of course dogged by massive guilt at the accident that he supposedly caused when he dodged the snowball that his friend threw at him and it hit Mrs. Dempster instead, triggering a premature labour and consigning her to madness. However, what is key for this chapter is the way that as Dunstable Ramsay grows up, his Presbyterian conscience causes him to feel constantly guilty for what he feels was his sin in causing Mrs. Dempster's madness. His interest in religion and in particular hagiography, or the lives of saints, causes him to identify Mrs. Dempster as his own personal saint, or a fool-saint, thanks to the definition provided by Father Regan:
...somebody who seems to be full of holiness and loves everybody and does every good act he can, but because he's a fool it all comes to nothing — to worse than nothing, because it is virtue tainted with madness, and you can't tell where it'll end up.
As the novel progresses it is clear that this governing symbol of the fool-saint is designed for a number of purposes: it allows Ramsay to replace her as simply the victim of his crime and view her as much more than that, and it also allows him to pedestal her as being some kind of model for Ramsay's life. The rest of the novel, particularly its concluding part, involves Ramsay's realisation of how it has been unhelpful for him to mythologise her and to attribute supernatural acts to her. The symbol of the fool-saint in this chapter is therefore strongly related to the theme of guilt and also Ramsay's response to that guilt.