Reason Over ion (French: La raison avant la ion) is a Canadian experimental film, directed by Joyce Wieland and released in 1969. A reflection on Pierre Trudeau's famous public statement that he valued reason over ion in his approach to governing Canada, the film deconstructs the concept by blending news footage of Trudeau at the 1968 Liberal Party of Canada leadership election with tracking shots of the Canadian landscape, as the letters in the subtitle "reason over ion" rearrange and scramble into 537 nonsensical anagrams over the course of the film.

The film was also indirectly linked to a quilting project that Wieland first exhibited in 1968, which included quilts stitched with both the English "Reason Over ion" and French "La Raison Avant La ion" mottos.