"Those who find ugly meanings in beautiful things are corrupt without being charming..."See in text(The Preface)
This is a direct jab at Victorians. Wilde was consistently criticized by prudish Victorians for his effeminate use of the word "charming" to describe things. To be "corrupt without being charming" is a message to his critics, telling them that they are ugly people as it is, with the added insult of the use of the word "charming" yet again. (See Oscar Wilde: his Life and Confessions by Frank Harris).
"The nineteenth century dislike of Realism is the rage of Caliban seeing his own face in a glass..."See in text(The Preface)
Victorians were quite hypocritical. On a societal level they preached virtue and prudishness, while poverty, opium dens, and prostitution grew more and more rampant. Wilde would have known this, as he was friends with Alfred Taylor, a notorious street chap who procured male escorts for upper class men (see The Trials of Oscar Wilde by H. Montgomery Hyde).
"All art is quite useless. OSCAR WILDE..."See in text(The Preface)
This celebrated and controversial statement embodies the aesthetic ideal that Art should not be used as a conduit of morality, judgement, or condemnation. To Wilde and the aesthetes, art is amoral. It exists merely for its own sake, "L'art pour l'art." Hence, when the word "useless" is applied to this statement it is used in its literary, and not in a contextual, meaning. Art simply is to be admired, not "used."
"immoral from the scientific point of view..."See in text(Chapter II)
This can be read as a hint at the new ideas of the 19th century regarding psychology, particularly the concept of the "basic Id," or the Freudian idea that mankind is inherently wild and immoral in nature.
"why I should not go in for philanthropy..."See in text(Chapter II)
During Victorian times, it was customary of the upper classes to spend time on philanthropy and charity. In Wilde's eyes, these attempts to show kindness were merely condescension and hypocrisy on the part of the rich.
Whitechapel was a notorious slum district in the East End of London. Inspired many works of literature including those of Charles Dickens. Think "Jack the Ripper," whose macabre murders paralyzed the area and made it even more notorious.
Contrary to popular misconception, Dorian Gray's character was not inspired by Lord Alfred Douglas, Wilde's most influential lover. Ironically and surprisingly, Douglas fits perfectly the description of Gray. However, Wilde had published this, his only novel, prior to meeting Lord Alfred. Dorian's character may have been inspired by John Gray, an up-and-coming poet quite popular among the aesthetes.
