Throughout the novel, Wilde only hints at the nature of Dorian's secret life, leaving the reader to wonder what sins Dorian commits. Wilde surely could have been more specific about Dorian's secretive passions, but he deliberately keeps the issue vague so that readers must define sin for themselves. In this way, Wilde draws readers closer to the story.
In a similar way, Wilde doesn't say what secret Dorian holds over Campbell. Most likely, it is something that the scientist did years ago while under Dorian's influence. In any case, Dorian is fully aware that blackmailing Campbell into helping him is dreadful, but he doesn't hesitate for a moment to do so. In fact, he scolds Campbell for not wanting to help him at first, and he even seems to take pleasure in forcing Campbell to comply eventually. Dorian has become dominated by the evil of his secrets, and he in turn seeks to dominate and control those around him. At this point in the story, Dorian shows that he has surpassed his mentor — Lord Henry — in his power to manipulate.
The interlude concerning Gautier's poetry works within the context of this novel. The poem is translated:
On a colorful scale,
Her breast dripping with pearls,
The Venus of the Adriatic
Draws her pink and white body out of the water.
The domes, on the azure of the waves
Following the pure contour of the phrase,
Swell like rounded breasts
Lifted by a sigh of love.
The skiff lands and drops me off,
Casting its rope to the pillar,
In front of a pink façade
On the marble of a staircase.
