What are the motifs in Vanity Fair by William Makepeace Thackeray?

Moral maturity is a recurring idea. Dobbin alone possesses real integrity and moral maturity, but even he is tinged with vanity. He is selfless, loyal, generous, and kind, ever content to give more than he takes. Dobbin's failure, similar to Amelia's, is his lack of discrimination about the characters of those around him. As a result, he gives people much more and much better than they deserve; in other words, he spends his life casting pearls before swine. And Dobbin's vanity lies in his dogged devotion to Amelia, who is, like the wares hawked at Bunyan's Vanity Fair, glittery but not golden.