Gaston Milhaud rejects the principle of contradiction if it is conceived as an absolute and universal rule. He claims that it only holds in some narrowly defined circumstances. According to him, the greater is mental contribution to an act of cognition the more appropriate is the application of the principle of contradiction. My analysis of his views shows that he wanted to emphasize the differences between the objective reality and its mental or linguistic representations rather than undermine the logical principle of contradiction. Parallels can be noted between Milhaud’s views on contradiction and Leon Chwistek’s theory of the multiplicity of realities, as well as Kazimierz Ajdukiewicz’s concept of the cognitive role of language.