The title suggests the idea: Vanity Fair. The treasures of Vanity Fair, that is, money and position, are desirable but transient. The gaiety, the mask of the ball, do not stay with the person when he faces death. Thackeray does not underestimate the importance of having a home, clothes and food; but he does expose the cruelty, the deception, the futility of making possessions and power the only aim in life.
The book is so saturated with the vanity of Vanity Fair, the duplicity of social climbers, and the weakness of human nature, that it would be impossible to separate idea from plot or plot from characters. If the book appears to ramble, it never strays from the focus of attention on the foibles of human nature in its struggle to reach the highest strata of Vanity Fair.
The setting could be changed to modern times and the observations would be true today. The vanity of man is universal and ever present. Women still berate and betray women; relatives still fight over money; mothers still sell their daughters for popularity, money, or position. Yet, there are some people, the reader hopes and Thackeray indicates, who do not bow down to the idols of Vanity Fair.
The winners at the end of the story are those who cherished human relationships first: Amelia, Dobbin, and Lady Jane, with the children Georgy and little Rawdon. Thackeray's idea, then, is that although one may live in Vanity Fair, one need not be a slave to its values, which in the final analysis turn into futility and emptiness. The reader feels that Georgy and little Rawdon will be better men than their grandfathers.