The work of Maupassant is part of the realism movement, the main literary movement of his time. Like Balzac, Flaubert, Goncourt and other French realist writers, everyday life is the focus of his themes, but in this case the view of reality is primarily pessimistic, even though the author often satirizes people and situations with a cheerful mood or deals with serious social problems. 

His target is always human stupidity, wherever it comes from (bureaucrats, clergy, bourgeoisie, farmers), as well as cruelty and inhumanity, vanity and selfishness. For Maupassant, man is "an animal somewhat superior to the others." However, in his mature works, there is a turn towards sympathy and understanding for simple people who suffer, being themselves victims of a harsh reality that crushes them.

The deterioration of his health gradually distances him from the detestable reality and leads him to the world of imagination, the nightmarish imagination. His last works, culminating in "Le Horla," are the result of a lived nightmare.