The book resembles another of Balzac's greatest novels, La Rabouilleuse (The Black Sheep, 1842), that is set in Paris and in the provinces.

The eventual title of Part III, Les Souffrances de l’inventeur (The Inventor’s Sufferings), was superimposed by Balzac onto his personal copy of the Furne edition of La Comédie humaine.

[3] Lucien Chardon, the son of a lower middle-class father and an impoverished mother of aristocratic descent, is the pivotal figure of the entire work.

Even as Part I of Illusions perdues, Les Deux poètes (The Two Poets), begins, Lucien has already written a historical novel and a sonnet sequence, whereas David is a scientist.

Lucien is introduced into the drawing-room of the leading figure of Angoulême high society, Mme de Bargeton, who rapidly becomes infatuated with him.

It is not long before the pair flee to Paris where Lucien adopts his maternal patronymic of de Rubempré and hopes to make his mark as a poet.

Mme de Bargeton, on the other hand, recognises her mésalliance and though remaining in Paris, severs all ties with Lucien, abandoning him to a life of destitution.

In Part II, Un Grand homme de province à Paris, Lucien is contrasted with the journalist Lousteau and the high-minded writer Daniel d'Arthez.

As a literary journalist he prostitutes his talent, yet still harbours the ambition of belonging to high society and longs to assume by royal warrant the surname and coat of arms of the de Rubemprés.

In Part III, Les Souffrances de l'inventeur, in Angoulême David Séchard is betrayed on all sides but is supported by his loving wife.

The lifestyle of the provinces is juxtaposed with that of the metropolis, as Balzac contrasts the varying tempos of life at Angoulême and in Paris, the different standards of living in those cities and their different perceptions.

[4] Balzac affirms the duplicity of all things, both in Paris and at Angoulême, e.g., the character of Lucien de Rubempré, who even has two surnames; David Séchard's ostensible friend, the notary Petit-Claud, who operates against his client, not for him; the legal comptes (accounts) which are contes fantastiques (fantastic tales); the theatre which lives by make-believe; high society likewise; the Abbé Carlos Herrera who is a sham priest, and in fact a criminal; the Sin against the Holy Ghost, whereby Lucien abandons his true integrity as a person, forging his brother-in-law's signature and even contemplating suicide.

There is the strong and perhaps somewhat artificial contrast between Lucien and David, art and science, Lousteau and d’Arthez, journalism and literature, Paris and the provinces, etc.

(5) Introduced into narrative fiction by the Gothic novel (The Castle of Otranto, The Mysteries of Udolpho, The Monk), melodrama was widespread in literature around the time when Illusions perdues was written.

[6] The success of this novel inspired Balzac to write a four-part sequel, Splendeurs et misères des courtisanes (published in parts from 1838 to 1847).

Illusions perdues and Splendeurs et misères des courtisanes form part of La Comédie humaine, the series of novels and short stories written by Balzac depicting French society in the period of the Bourbon Restoration and July Monarchy (1815–1848).