Dorian tells Henry that he has reformed. From now on, he is going to do good actions rather than bad. He tells Henry he was seeing a simple village girl named Hetty and was in love with her. They were planning to go away together, but Dorian decided to call it off, so that she would not have to be involved with someone as disreputable as himself. Henry is not impressed, but Dorian insists that it is the first good action he has done in years. He calls it an act of self-sacrifice.
The subject of Basils disappearance comes up. No one knows what happened to him. The French police declare that he never arrived in Paris. Henry also mentions that Alan Campbell has committed suicide and that his, Henrys, wife Victoria ran off with another man. When Dorian asks him if he thinks Basil was murdered, Henry dismisses the idea. Dorian asks him what he would say if he told him that he, Dorian, had murdered Basil. Henry replies that Dorian is incapable of murder.
Henry asks Dorian to play a Chopin nocturne on the piano. While Dorian plays, Henry speaks at length about life. He asks the younger man how he has managed to stay so youthful, and he admits to having sorrows that Dorian knows nothing of. He thinks Dorian has led an exquisite life, but Dorian knows better. He repeats that he intends to change his life, and reproaches Henry for lending him the book that exerted such a profound but bad influence on him.
They agree to meet at eleven the following morning.
When Dorian returns home he sits in the library contemplating his corrupt life. He wonders whether there is any hope for him. He loathes his own beauty, but then decides not to think of the past, which cannot be altered. He once again resolves to live a good life. He goes upstairs to see if the picture has registered his new desire to be good. But there is no change; the face is still loathsome. What should he do? Should he give himself up and confess to the murder? Who would believe him? He decides to destroy the picture, which is the only piece of evidence against him. He takes the knife with which he had stabbed Basil, and stabs the picture with it. There is a cry and a crash. The alarmed servants go upstairs and find the perfect portrait of Dorian in all his youth and beauty, while Dorian lies dead on the floor with a knife in his heart. He is withered and wrinkled.
Chapter 19 shows a rather different Lord Henry than has been revealed up to now. He seems tired and regretful, aware of lost youth (“I am wrinkled, and worn, and yellow”). Instead of firing off epigrams and delighting in being outrageous (as he does at the Duchesss of Monmouths party in chapter 17), he seems more sincere and reflective. It becomes clear that Henry is not being held up as an ideal. He cannot see what Dorian has become as a result of following Henrys philosophy of life. He does not understand Dorian at all. He thinks that if Dorian were to confess to a murder, he would be “posing for a character that doesnt suit [him],” since Henrys theory is that only the lower classes commit crimes. There is an unconscious irony in Henrys words that “The things one feels absolutely certain about are never true.” Henry also lacks perceptiveness. He thinks Dorian has lived up to the ideal that Henry has tried to show him: “You have crushed the grapes against your palate. Nothing has been hidden to you. And it has all been to you no more than the sound of music. It has not marred you. You are still the same.” The first part is correct, the second wildly inaccurate, as the picture reveals. Dorian has been terribly marred by his experiences, but Henry is unable to see it. The effect on the reader of seeing Henry so out of touch with reality is to bring into question his entire philosophy, and encourage a second, more critical look at the dazzling epigram-making Henry of the early chapters. For all his apparent worldly wisdom, Henry seems to lack a real understanding of life.
Tormented until the end, Dorian realizes that even his attempt to reverse the direction of his life, by renouncing Hetty Merton to spare her the pain of being involved with him, was an act of vanity not goodness. He was simply curious about what an act of self-denial would feel like. But his clear-sightedness does not extend to his act of murder. He does not seem to believe it was wrong and feels no desire to confess. Instead, his last act is an attempt to destroy what he believes is the only evidence against him. He thinks he can kill the past and attain peace. But this is an illusion. In striking at the picture, he is attacking himself, since the picture reflects the true state of his soul. He cannot escape the consequences of his deeds. He has lived the life that he wanted to live, but has paid a terrible price for it.