A non sequitur (/ˌnɒnˈsɛkw[invalid input: 'ɨ']tər/; Latin for not sequence meaning it does not follow) is a conversational and literary device, often used for comedic purposes. It is something said that, because of its apparent lack of meaning relative to what preceded it,^[1] seems absurd to the point of being humorous or confusing.

This use of the term is distinct from the non sequitur in logic, where it is a fallacy.

Literally, the expression is Latin for "it does not follow."^[2] It comes from the words "non" meaning not, and the deponent verb sequor, sequi, secutus sum meaning 'to follow,' thus producing sequence and second. (Deponent verbs have passive forms but active meanings.)

A non sequitur can denote an abrupt, illogical, unexpected or absurd turn of plot or dialogue not normally associated with or appropriate to that preceding it. A non sequitur joke has no explanation, but it reflects the idiosyncrasies, mental frames and alternative world of the particular comic persona.^[3]

The non sequitur can be understood as the converse of cliché. Traditional comedy and drama can depend on the ritualization and predictability of human emotional experiences, where the Theatre of the Absurd uses disjunction and unpredictability. The use of non sequitur in humor can be deliberate or unintentional.^[4]

• “A woman needs a man like a fish needs a bicycle.” ― Irina Dunn
• “It tastes like somebody stole my wallet. Ya know?” ― Gerard Way
• “Sleeping in a tinfoil suit keeps me warmer and helps prepare me for my voyage to the moon. Would you care for some licorice?” ― Jarod Kintz
• “It was a spring day, the sort that gives people hope: all soft winds and delicate smells of warm earth. Suicide weather.” ― Susanna Kaysen
• “If I had to live my life over, I'd live over a saloon.” ― W.C. Fields
• “Nice dress,” Victoria said. “Thank you,” Perpetua said. “Do you mind if I ask you a personal question?” Victoria blinked. “Uh, what?” ― Benjamin R. Smith
• “If you ask, What is a non sequitur? And I say, “Blue love on a blue moon on Mr. Green’s greenback printing machine (the one that sounds like Weimar Germany in 1923)”, then I have given you an example of a non sequitur. But since you asked what a non sequitur was, the fact that I gave you a non sequitur as an answer means it most definitely is not a non sequitur, since it does follow logically. Because it is means that it isn’t. But because I gave you what you wanted, when you wanted what you didn’t want, then I didn’t give you what you wanted, thus giving you what you wanted. So it is a non sequitur, which means it isn’t. But since it isn’t, when you expected it to be one, signals that it is. So it is and it isn’t, all at the same time!” ― Jarod Kintz
• “I had a dream about you coming up with non sequiturs. You were a purple giraffe and I was an orange rhino. But we were eating liquid skittles.” ― Ryan Lilly

• Anacoluthon
• Absurdity
• Antihumour
• Dadaism
• Gibberish
• Randomness
• Surreal humour
• Derailment (thought disorder)

• The Comprehension of Humorous Materials by Adolescents with High-Functioning Autism and Asperger's Syndrome - "Non sequitur endings or incorrect endings that are unrelated to the content of the joke were preferred by adults with high-functioning autism"
• Getting it: human event-related brain response to jokes in good and poor comprehenders - "When asked to pick the punch-line of a joke from an array of choices, including straightforward endings, non-sequitur endings, and the correct punch-line, RHD patients erred by picking non-sequitur endings, indicating that they know surprise is necessary"