Les Non-Dupes Errent

Building on Freud's The Psychopathology of Everyday Life, Lacan long argued that "every unsuccessful act is a successful, not to say 'well-turned', discourse", highlighting as well "sudden transformations of errors into truths, which seemed to be due to nothing more than perseverance". In a late seminar, he generalised more fully the psychoanalytic discovery of "truth—arising from misunderstanding", so as to maintain that "the subject is naturally erring... discourse structures alone give him his moorings and reference points, signs identify and orient him; if he neglects, forgets, or loses them, he is condemned to err anew".

Because of "the alienation to which speaking beings are subjected due to their being in language", to survive "one must let oneself be taken in by signs and become the dupe of a discourse... [of] fictions organized in to a discourse". For Lacan, with "masculine knowledge irredeemably an erring", the individual "must thus allow himself to be fooled by these signs to have a chance of getting his bearings amidst them; he must place and maintain himself in the wake of a discourse... become the dupe of a discourse... les Non-dupes errent".

Lacan comes close here to one of the points where "very occasionally he sounds like Thomas Kuhn* (whom he never mentions)", with Lacan's "discourse" resembling Kuhn's "paradigm" seen as "the entire constellation of beliefs, values, techniques, and so on shared by the members of a given community" – something reinforced perhaps by Kuhn's approval of "Francis Bacon's acute methodological dictum: 'Truth emerges more readily from error than from confusion'"

*Thomas Samuel Kuhn (pron.: /ˈkuːn/; July 18, 1922 – June 17, 1996) was an American physicist, historian, and philosopher of science whose controversial 1962 book The Structure of Scientific Revolutions was deeply influential in both academic and popular circles, introducing the term "paradigm shift", which has since become an English-language staple.

Kuhn made several notable claims concerning the progress of scientific knowledge: that scientific fields undergo periodic "paradigm shifts" rather than solely progressing in a linear and continuous way; that these paradigm shifts open up new approaches to understanding that scientists would never have considered valid before; and that the notion of scientific truth, at any given moment, cannot be established solely by objective criteria but is defined by a consensus of a scientific community. Competing paradigms are frequently incommensurable; that is, they are competing accounts of reality which cannot be coherently reconciled. Thus, our comprehension of science can never rely on full "objectivity"; we must account for subjective perspectives as well.

- Wikipedia

The phrase qui pro quo, or quiproquo (from medieval Latin: literally qui instead of quo), is common in languages such as Italian, Portuguese, Spanish and French, where it means a misunderstanding.