In the book Dr. Jekyll and Mr. Hyde...?

I think you will probably find your answer in Chapter 10: http://www.steve-calvert.co.uk/public-domain-texts...

Jekyll considers himself to be agood man. Hyde is his evil alter-ego and Jekyll knows how evil Hyde is, yet he willingly allows the transformation. It seems to me that Jeckyll enjoys--at least to a certain extent--being Hyde because, hiding behind the face of a monster, he can do what he wants without having to live with the consequences. Surely a truly good man would not want to do such things in the first place. Hyde is in some ways just a mask.

I'm not sure if this is the answer you are looking for, but chapter 10 contains plenty of food for thought and it certainly got me thinking.

It relies upon on what subject matter you're speaking approximately. in case you advise the character of evil, then attempt: "Dracula" - Bram Stoker "Clockwork Orange" - Anthony Burgess "Crime and Punishment" - Fyodor Dostoevsky "Lord of the Flies" - William Golding "heart of Darkness" - Joseph Conrad