Novelists aren’t supposed to introduce new characters at the end of a book, and the person who’s been standing across from Sarah’s house during the last scene seems like a violation of this rule. However, he’s forced his way into the story because he can’t stand to not be important. It’s possible that he was somewhat falsely portrayed earlier in the story. His true nature is unpleasant. He’s changed his appearance since he was in the train compartment, and now he looks like an opera manager. He seems amused, and is watching Mr. Rossetti’s house as though he owns it. In general he seems to think he can do what he wants with the world. He takes out his watch and sets it back by fifteen minutes. Surely he’s giving himself an excuse for lateness. He beckons to a carriage and gets in. It drives away.
Fowles again satirizes himself in the form of the narrator. This narrator is a slightly different incarnation than the one earlier in the book, perhaps an incarnation that is more inclined towards making his characters miserable than towards giving them happy endings. He gives the sense that he’s in control of this world because he is, more or less; it’s as though a god is controlling life from the ground. There’s an illusion here that the narrator on the street isn’t actually the narrator writing, since the narrator writing pretends not to understand that setting the watch back will actually set the characters’ timeline back.
Charles says Sarah has gained pleasure from hurting him, and she will go to hell for it. He makes to leave the room, but she calls to him. He looks back over his shoulder. She says this proves that they should never have met again. Charles says he didn’t understand her true selfish nature, and that she’s far worse than Mrs. Poulteney. Sarah asks whether she wouldn’t be selfish if she let him marry her though she can’t love him. Charles says their positions are reversed from the time when he was her only hope. This is his most powerful but cruel argument, and now he opens the door.
This is the second possible ending of the story (third, if you count the conventional Victorian one that Fowles proclaims to be false), which the narrator promised earlier. As it comes second, the reader is clearly expected to compare it to the first ending, though not to judge either one as being truer. Here, Charles recognizes that he and Sarah have switched places in the world, and saying so means that Sarah has to grapple with having made someone as miserable as she used to be.
Sarah says Charles’s name again, and puts her hand on his arm. He stops. It seems like her gesture is meant to tell him something. He looks at her slowly and sees that her eyes are smiling at him. He wonders if she’s telling him to lighten up or if she’s gloating. Her hand on his arm seems to say that there’s a solution. He realizes what it is, and her hand drops. It seems like they can suddenly see all each other’s faults. Charles can tell that Sarah is willing to sacrifice everything to save the integrity of her spirit. Sarah realizes she’s made a mistake, and if he accepts her offer of friendship it will hurt her more than anything. Charles sees how he would be teased by everyone in this house, and he sees that he’s superior to her in his ability to compromise, whereas she can only possess and must always be possessing.
Charles seems to believe that in this gesture, Sarah is offering that they could be friends, that they don’t have to choose between marriage and complete estrangement. But friendship of this sort isn’t possible in this society, particularly when Charles and Sarah have slept together and have endured so much censure for their relationship. Furthermore, being friends would emasculate Charles. In this iteration of the story, Charles can find nothing redeeming in Sarah; he sees her only as a morally corrupt and voracious woman who will stop at nothing to gain power over other people.
Sarah has always manipulated Charles, and she knew that he would reject her offer. He leaves the room. He wants to cry but refuses to do it in this house. The girl who greeted him appears, carrying a child, but Charles leaves before she can speak. He doesn’t know where to go. He feels he has to start everything over. In the distance, he sees a carriage going out of sight. Looking at the river, he sees all of his life has been for nothing, and he will never love again. He turns back to the house and thinks he sees a curtain fall. But in reality, Sarah is still in the studio, looking into the garden, where a child and a young woman sit.
Because Fowles put the other ending first, the reader knows that this moment in which Charles sees the child is an essential moment of loss, as he’ll never know that she is his daughter. However, it’s actually unclear whether the child is his daughter in this iteration, or if she belongs to the woman who’s holding her. In any case, his relationship with Sarah is over, and it seems to have ruined his life and all been for nothing, though it took up an entire book.
It may seem that Charles was foolish not to accept Sarah’s offer of friendship, and that the offer showed some weakness in Sarah. It may seem that Sarah’s battle was a righteous one against an invader. But the reader must believe that this ending is just as realistic as the former one. The narrator has returned to the principle that evolution is the only god that influences human life, and so humans have made their own lives by acting to reach their goals. Humans are guided by acting what they know, as Matthew Arnold put it, and this has guided Sarah. Charles paces along the river, and it may seem that he’s about to kill himself, but he has in fact finally found faith in himself. He’s beginning to realize that life isn’t a single symbol or riddle, but something to be endured.
The narrator is careful not to make any moral judgments in reflecting on this ending, and he insists again that either ending is possible. Evolution, the everyday struggle for survival, the struggle to get what one wants, rules human actions, and there is no overarching moral or divine reason for the way that history proceeds. The narrator implies that Sarah has been the most authentic character, because she never pretended that she was guided by anything other than her personal experiences and desires. Charles, for his part, now understands in a rather existentialist way that he must accept his lack of understanding and move on into his loneliness.