 Stuewe described the book as "perhaps the best popular book on existentialism".Pulver identified the book as an influence on filmmaker Woody Allen, observing that the title of his film "Irrational Man" (2015) is clearly inspired by Barrett's book, which "no doubt formed part of Allen’s self-taught intellectual life in the late 50s and early 60s".The theologian John Macquarrie described "Irrational Man" as one of the most useful books about existentialism.