While admitting that Lacan ‘was brilliant’ and ‘a friend’, Julia Kristeva offers a sustained and radical critique of his conceptual framework and, by extension, his concept of the subject. She claims that, despite his protestations to the contrary, Lacan proposes ‘a theory of the subject as a divided unity which arises from and is determined by lack (void, nothingness, zero, according to the context)’, before going on to explain that ‘[t]his subject, which we will call the “unitary subject,” under the law of One, which turns out to be the Name-of-the-Father, this subject of filiation or subject-son, is in fact the unvoiced part’. There are two aspects to this that Kristeva finds troubling. First, while he affirms a divided subject, Lacan is charged with implicitly encasing this division within a unity, with the consequence that he remains bound to and perpetuates the privileging of unity inherent in the Cartesian tradition. Second, Kristeva points out that the Lacanian subject is an effect of the repression imposed on it by the symbolic father, a conceptualisation that radically downplays the role of the mother in fostering the child and, indeed, offers a troublingly one-dimensional account of the father that sees ‘him’ only in terms of authority.

To correct this, she continues to affirm the psychoanalytic division between the unconscious and conscious, but complicates the ways in which these two ‘realms’ are conceptualised and, indeed, how they relate to one another. To do so, she first turns away from Lacan's insistence that the unconscious is structured like language to Freud's insight that the unconscious is tied to drives. These drives are differentiated and in constant, heterogeneous movement, thereby disrupting any notion of a fixed foundation for the subject. For Kristeva, it is the drives, not language, that ‘introduce’ difference ‘into’ the psyche.

Second, she criticises Lacan's claim that language is tied to the symbolic, which she understands to entail conceptual signification, instead holding that symbolic language is tied to another form of non-conceptual signification, termed the ‘semiotic’.