Richardson wrote to his friend Isabella Sutton on July 24, 1752,
I have had two letters from Miss Mulso, admirable ones. She particularly commends herself to your favour. I have threatened her with a melancholy ending of my story. O how she raves! almost execrates me! I want to shew you fresh instances of her admirable genius though against myself; and I want to let you see Greville just ready with his dagger; but I will say no more. What scenes of distress might be painted! but did I not say, I would not proceed on this subject?
Greville is an expressive mood-object, a poltergeist: he makes the book more frightening; produces gestures but never enforces them. Sir Hargrave Pollexfen is the ghost’s solid: he acts, he suffers, isn’t playful and plots real sexual violence (does not press impressions on hands). While he is helping his friends carry out a seduction he is caught by Italian revengers who would have castrated him if Grandison hadn't appeared in the nick of time (vol. 4, ch 36). This scene offers itself up as an obvious counterpoint to the earlier rescue of Harriet from Pollexfen himself (vol. 1, ch. 33), but there are so many ways to read the existence of this mirroring that I find I can’t say what I think it should ‘mean.’ As an event it fuels the cycle of events, but as a mirror it has no lessons and appears like a blank.
Grandison’s character is illustrated more than once by his willingness to manifest in certain situations, e.g., when Pollexfen invites him to breakfast (vol. 2, ch 3) – a trap, as Grandison knows – but Grandison comes nonetheless, refusing to be teased into a duel in front of Pollexfen’s friends; he will set his own conditions for appearing. Calmly he tells everyone why he will not duel. They understand. He has “shewn that reputation and conscience are entirely reconcilable,” they say. When he appears in front of the Italian family that has contentious feelings towards him he will set his own conditions there too. It is part of Richardson’s plan for his magnificence, him being able to impose himself reasonably. Harriet you notice cannot lay out her terms; she can’t say that she loves him. As her marriage draws closer she has progressively more trouble appearing and speaking. She hesitates over her own marriage ceremony, she wants it put off; she does not want to marry in front of people. She fails to finish sentences or she remains quiet and curtsies instead (vol. 6., multiple places). Even as she is married, “My joy may not be sufficient to banish fear” (vol. 7, ch. 6). Why does she feel this weird terror? In vol. 6, ch. 32 it is bad enough to give her nightmares. She says that Grandison should marry the superb and good aristocrat Clementina della Porretta, not her. Harriet has never met Clementina but at no point does she suspect that the people who tell her about Clementina's goodness might be exaggerating. You could say that Harriet is having a dream of a perfect woman, but later they meet and there is no difference between the Clementina in the reports and the real one. One letter from anybody was enough to describe her as she is.
Harriet is fortunate. She is marrying the right man and everyone envies her. Horror, humility, and depression, this is what, however, for some reason, Richardson decides he will describe for her, as if she is going through a terrible incident; as if something bad has happened. What does she want? She wants something that is not sensible.
Richardson, in his letter, relishes the thought of Miss Mulso being not-sensible, being filled with desire for she doesn't-know-what, "but I will say no more,"