The principle of immanence is often poorly considered : most people who still refer to it hasten to add how it is difficult it is to do so, and how their attempts to account for it are likely to bring about heuristics gains. The centenary of the CGL is a great opportunity to return to the sources of the principle of immanence in linguistics and semiotics, and to follow its progress in Saussure, then in Hjelmslev’s interpretation of Saussure, and finally in Greimas’s interpretation of Saussure and Hjelmslev. We have to remind ourselves in particular why, for Saussure and Hjelmslev, immanence is inseparable from the definition and delimitation of a cognitive object belonging to a discipline that seeks to define its place among the existing disciplines. And we aim primarily to show how, in Saussure, immanence accommodates a permanent invention of semiosis within the sign, and then, in Hjelmslev and especially in Greimas, how it becomes even a creative constraint in the postulated and observed gap between manifestation and immanence, and between generated and attested manifestation. The principle of immanence becomes a scientific strategy that allows Saussure to articulate formality and sociality, while for Hjelmslev it allows for the articulation of generativity and creativity, and for Greimas that of veridiction and invention of semiosis.