What literary devices are used in The Picture of Dorian Gray?

In The Picture of Dorian Gray, Wilde uses a number of literary techniques to develop his characters and to enhance some of the novel's key themes.

Allusions, for example, are widely used in Chapter One to reveal more about Dorian's appearance and character. He is likened to Adonis, a man of great beauty from Greek mythology, to demonstrate his visual appeal to the reader. He is also likened to Narcissus, another figure from Greek mythology, who fell in love with his own image and died because he could not stop looking at himself in the reflection of a pond. By including this allusion, Wilde also foreshadows Dorian's future and suggests that his self-love will develop into an unhealthy obsession.

Wilde also uses a number of symbols in the novel. The portrait, for example, becomes a living representation of Dorian's soul which degrades as his levels of vice and immorality increase.  It also represents the unavoidable process of ageing which Dorian is so keen to prevent. In addition, the yellow  book, given to Dorian by Lord Henry, is another important symbol because it demonstrates Lord Henry's corrupting influence on the young Dorian.

Witty sayings, called epigrams, are also an important feature of Dorian Gray. They not only enhance Wilde's lively writing style but also reveal much about the character of Lord Henry. He uses them, for example, to add a humorous element to his negative views on women:

Women are a decorative sex. They never have anything to say, but they say it charmingly.

That Dorian emulates Lord Henry's use of epigrams illustrates the extent of the latter's influence. One example comes from Chapter Four when Dorian speaks of Sybil Vane:

Ordinary women never appeal to one's imagination. They are limited to their century.

Furthermore, these epigrams are often ironic or paradoxical in nature:

There is only one thing in the world worse than being talked about, and that it not being talked about.

This use of irony suggests that Lord Henry and Dorian are superficial people; they are driven by a need to appear to be witty and intelligent. Dorian captures this idea in Chapter 19:

You would sacrifice anybody, Harry, for the sake of an epigram.

Unfortunately, Dorian's realisation comes too late: he cannot be redeemed from his life of vice and corruption as we see most clearly in his untimely demise.

What are the language features of The Picture of Dorian Gray?

Composed much more of dialogue than lengthy descriptive sentences, Oscar Wilde's The Picture of Dorian Gray is more a drama than it is a novel. The brevity of description is often covered in the witty and warm conversations of the characters such as the dissolute Lord Henry who constantly emits sparks with his gentle satire on different elements of society.  For instance, in his conversation with the artist, Basil Hallward, who tells Lord Henry about his sensations that his soul and art were "absorbed" upon his first encounter with the beautiful Dorian Gray, Lord Henry reacts,

Conscience and cowardice are really the same things, Basil.  Conscience is the trade name of the firm.  That is all.

Marriage, women, faithfulness, romance, humanity, stupidity, and even weather are all topics for the "sharp and sweet tongue" of Lord Henry's epigrams.  His ease of expression creats vivid images in the mind of the reader, who gains a greater insight into Wilde's intent.

As critic Richard Ellman writes in an introduction to The Picture of Dorian Gray,

The book is his parable of the impossibility of leading a life on aesthetic terms. 

Through the actions and speech of Dorian Gray, Wilde shows that a life supposedly free of conscience and duty never is.  Gray self-indulgence exceeds conscience and he vandalizes his own portrait to cover his sins, thus sacrificing his own life.

The most salient language features, then, are epigrams.  With the parable of Dorian Gray, there are the underlying myths of the fall of man, the legend of Faust with Lord Wotton playing the role of Satan, and, of course the tale of Narcissus as Dorian Gray, indeed, falls in love with himself.  All of these tales underscore Wilde's "disclaimer" in the preface of his novel that "no artist has ethical sympathies...All art is at once surface and symbol."