there might have been some sense in it. He could have said, as Basil did, that it might have simply been an off night for her and that a woman's acting talent is only one small thing of many good qualities a man can be attracted to and for which he can love a woman. Yet nothing of the kind is said by Henry, or even by Basil. The oddity is that when Henry says, "Let us go, Basil," we are told it is with a "strange tenderness in his voice."

Overall, it is not so much anything specific said by Henry and Basil, but the generally self-important and pompous way the two, especially Henry, comport themselves that makes Dorian so embarrassed by Sibyl's performance. It is after Sibyl's death that Lord Henry begins to work on Dorian, bombarding him with superficial and cynical phrases that are partly meant to comfort him, but have the effect of making all of life seem a joke. In chapter 8, Henry says, "You musn't let this thing get on your nerves. You must come and dine with me, and afterward we will look in at the opera." This is partly to protect Dorian so that the police will have no suspicion he may have been mixed up in the girl's death, but it is also to make Dorian think that the death of one he loved is meaningless, and that one should just forget about it and move on. Later, Henry says, "But really, Dorian, how different Sibyl Vane must have been from all the women one meets! There is something to me quite beautiful about her death. I am glad I am living in a century when such wonders happen." The coldness of this is supposed to be mitigated by the pleasant way it is phrased, but it's clear that Henry is trying to convert Dorian to his brand of amorality. Henry is tiresome in spite of his wit, and one wishes he would shut up for once.

A more central thing than Henry's words which tempt Dorian to abandon moral sense is the book he gives Dorian to read in chapter 10:

It was a novel without a plot, and with only character, being, indeed, simply a psychological study of a certain young Parisian who spent his life trying to realize in the nineteenth century all the passions and modes of thought that belonged to every century but his own, and to sum up, as it were, in himself the various moods through which the world spirit had ever passed, loving for their mere artificiality those renunciations that men have unwisely called virtue, as much as those natural rebellions that wise men still call sin.

Later, Dorian says about the book "I didn't say I liked it...I said it fascinated me. There is a difference." Henry replies, "Ah, you have discovered that?" Both the book and Henry's comment are an encouragement to Dorian not to live the life he likes and knows is correct, but one which fascinates him, no doubt like the book does, in an amoral way.

In The Picture of Dorian Gray by Oscar Wilde, the unsuspecting Dorian Gray is lured by the detached, but highly influential Henry Wotton, who treats Dorian as nothing more than a real-life experiment. From the beginning, he watches, unaffected, as Dorian goes to extraordinary lengths to preserve his youth. There are many instances which reveal that Henry Wotton is instrumental in Dorian Gray's downfall and an understanding that he, himself, would never go to such lengths and would rather watch the effects on Dorian:

"To get back my youth I would do anything in the world, except take exercise, get up early, or be respectable."

However, it is Henry's expression of what are essentially his own desires that create the recognition or the feelings of potential loss in Dorian and Henry finds fulfillment watching Dorian be what Henry, himself, cannot be. Henry overwhelms Dorian, who tries, "not to think," because:

"The few words that Basil's friend had said to him-... had touched some secret chord that had never been touched before, but that he felt was now vibrating and throbbing to curious pulses."

Henry knows how he can manipulate Dorian and, "having shot an arrow in the air," meaning that he has merely made a suggestion, which, for Dorian's impressionable mind is enough, he can take advantage of Dorian's  weakness and level of trust. Henry makes a huge impression on Dorian, convincing him that, once his good looks are affected by age, he will become "bitter" and this will bring him "nearer to something dreadful." He persuades Dorian:  

"The moment I met you I saw that you were quite unconscious of what you really are, of what you really might be. There was so much in you that charmed me that I felt I must tell you something about yourself. I thought how tragic it would be if you were wasted. For there is such a little time that your youth will last--such a little time."

The influence that Henry has on Dorian becomes apparent very quickly. Even Basil cannot believe the change in his friend. He is shocked at Dorian's new outlook: 

 "Lord Henry Wotton is perfectly right. Youth is the only thing worth having. When I find that I am growing old, I shall kill myself."

Basil knows how manipulative "Harry" - Henry Wotton- is and knows his association with the young Dorian cannot be good, especially as Henry believes such things as, "Sin is the only real colour-element left in modern life." When Dorian goes to dinner with Henry, rather than stay and dine with his friend who entreats him to stay, Basil knows that Henry will exert his power over Dorian, even without Dorian being aware of it,which is why "the painter flung himself down on a sofa, and a look of pain came into his face."