the plastic use of the letter or sign would not signify anything other than itself

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In the plastic field, Lettrism is based on the merging of image and word. The plastic use of the letter or sign would not signify anything other than itself, thus transcending traditional conventions of meaning by emphasising the form of the letter over representation. Isou conceived Lettrism as fundamentally different from movements that preceded it, representing a complete shift from figuration and abstraction to the plastic use of the symbol of letters or signs. While Isou acknowledged that some artists associated with the Bauhaus and Cubism, and artists such as Marcel Duchamp, approached qualities of Lettrism, Isou declared that these artists ultimately faltered by subjecting letters to function and burdening them with meaning, rather than granting them independence and allowing them to become pure form.
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