Intentional fallacy is a literary term asserting that the meaning intended by the author of a literary work is neither the only, nor even necessarily the preferred, meaning of the piece.
An author must call upon both her understanding of the language in which she writes and her personal experiences about reality to create a work. Even the most escapist fantasy must appeal to some shared understanding in the reader to be intelligible at all.
Correspondingly, a reader must call upon his understanding of language and personal experiences in order to decode meaning in a work.
A literary work may thus be looked at as an attempt by an author to a communicate to a reader via a shared language and via having shared experiences with the reader. Without a common ground, communication is labored or impossible.
But the author and the reader will inevitably have different personal experiences, and therefore hold different beliefs and opinions about what different aspects of reality mean, and their relative importances.
Because of these differences the meaning taken by a reader is always only approximately the meaning intended by the author, and also only approximately the meaning taken by other readers.
Further complicating communication, both the author and the reader may be unaware of peculiarities in their undertanding of reality, and these peculiarities may color either the work as written or the meaning taken by the reader in ways unconscious to either.
For example, a work written during the Post-World-War-II era may exhibit commonly-held views of the time, such as prejudices concerning Germans or Japanese. A modern reader might disagree with these prejudices, and see newfound meaning in reviewing how these prejudices color the work. And literary criticism has found that this newfound meaning is not merely a curious quirk, but a valuable means of gaining insight into a work.
Because of these inevitable differences between an author and her readers, it is thus held to be a fallacy that the author's intentional crafting of content is the only meaning in a work.