Along with Constantin François Chassebœuf de Volney (1757–1820) Dupuis was known for developing the Christ myth theory, which argued that Christianity was an amalgamation of various ancient mythologies and that Jesus was a mythical character.
Sammen med Constantin François Chassebœuf de Volney (1757-1820) var Dupuis kendt for at udvikle Kristus myte teorien, som hævdede, at kristendommen var en sammenlægning af forskellige gamle mytologier, og at Jesus var en mytologisk karakter.