In what way is Dorian's character dramatically different in Chapter Nine?

In Chapter Nine, Dorian's character has changed in two ways. 

Firstly, Dorian demonstrates a striking resemblance to Lord Henry. This is best shown in his comments to Basil about Sybil's death in which Dorian uses witty expressions, called epigrams. Here are some examples:

• "If one doesn't talk about a thing, it has never happened."


• "A man who is master of himself can end a sorrow as easily as he can invent a pleasure."

The use...

In Chapter Nine, Dorian's character has changed in two ways. 

Firstly, Dorian demonstrates a striking resemblance to Lord Henry. This is best shown in his comments to Basil about Sybil's death in which Dorian uses witty expressions, called epigrams. Here are some examples:

• "If one doesn't talk about a thing, it has never happened."


• "A man who is master of himself can end a sorrow as easily as he can invent a pleasure."

The use of such epigrams demonstrates the strength of Lord Henry's influence on Dorian as well as Dorian's increasing moral decay: he is unaffected by Sybil's death because she no longer serves his needs. 

Secondly, this chapter shows another important change in Dorian; that is, his changing attitude towards the portrait. In Chapter One, for example, Dorian was intensely jealous of his portrait because of its ability to stay young and beautiful forever. By Chapter Nine, however, Dorian is terrified of Basil showing the portrait to the public because he knows it will reveal his corrupted morality: 

Was the world going to be shown his secret? Were people to gape at the mystery of his life? That was impossible. Something - he did not know what - had to be done at once. 

This, in fact, foreshadows Basil's murder later in the novel and shows, beyond all doubt, the full extent of Dorian's need for self-preservation.