It is hard to think of many contemporary European philosophers who have not endorsed the denunciation of existentialism for being a humanism that was initiated by Heidegger and has been perpetuated in the anti-humanism of structuralists such as Louis Althusser and Roland Barthes. Concerned with the way in which both languages and systems produce individuals as subjects, structuralism took over from existentialism both academically and perhaps even in terms of public attention. Structuralism sought to arrive at a stable and secure knowledge of a system or a structure by charting differences within that structure and, significantly, it sought to do so without any references to subjectivity and consciousness, which were, as we have seen, a significant part of existential phenomenology.
However, it was not long before structuralism was itself being challenged by poststructuralism in the late 1960s. Philosophers such as Michel Foucault (at least in his middle and later work), Jean-François Lyotard, Gilles Deleuze and Jacques Derrida were all important in this regard, challenging the “centrist” assumption of structuralism that an understanding of one key or central element of the structure – whether it be kinship laws, the workings of language, the educational system, or the devices employed in a literary text – allows for an explanation of the entire system. Poststructuralism also cast into question structuralism's rather strict determinism, instead insisting on the role of unpredictable and random forces in the genesis of any structure, law or norm.