Differentiality
ELI5
Differentiality is the idea that things don't have their own built-in identity — they only mean something because of how they're different from everything else around them — and that even a missing thing can count as a real, present feature in that system of differences.
Definition
Differentiality, as coined in this passage from Žižek's reading of Saussure, Lacan, and Hegel, names the logical structure whereby identity is constituted not through positive, self-contained properties but exclusively through relations of difference within a system. The key theoretical move is to push this insight past its structural-linguistic starting point: if a signifier has no being of its own outside of the differences that distinguish it from all other signifiers, then the absence of a feature is not merely a privation but can itself function as a positive, operative mark. Differentiality is therefore the name for the paradox that presence and absence are no longer opposites but belong to the same logical matrix — absence counts as a feature, a "positive fact," within the differential network.
In Žižek's argument, differentiality serves as the shared deep structure — the "logical matrix" — that articulates three otherwise distinct traditions: Saussurean structuralism (identity as differential), Hegelian dialectics (negation/absence as constitutive of determination), and the Lacanian symbolic (lack as structural rather than empirical). This logical matrix is also what grounds Miller's concept of suture: the subject is not an external observer of a differential structure but is itself the "presence of absence" that holds the structure together — a void that is inscribed as a positive element inside the chain. Against Badiou's asubjective structuralism and deconstructionist dispersal of the subject, differentiality insists that the subject belongs to the structure precisely as its constitutive lack.
Place in the corpus
In slavoj-zizek-less-than-nothing-hegel-and-the-shadow-of-dialectical-materialism-v, differentiality functions as a pivot concept in Žižek's broader effort to show that structuralism, Hegelian dialectics, and Lacanian psychoanalysis are not competing frameworks but convergent formalizations of the same ontological discovery: that negativity (lack, absence, negation) is not the opposite of positivity but its very condition of constitution. The concept is thus continuous with — and in important respects a generalization of — several cross-referenced canonical concepts. It most directly underpins Lack: where lack names the specific Lacanian designation of the void that structures desire and the subject, differentiality provides the formal-logical ground that makes such a lack operative rather than merely empty. Lack is, so to speak, the psychoanalytic name for differentiality's defining paradox. Similarly, differentiality connects to Alienation: if the subject has no positive self-identical being but is constituted only differentially — through its place in a chain it did not originate — then alienation in the Lacanian sense (constitution through the Other's signifying field) is not an accident but the direct consequence of differentiality applied to subjectivity.
Differentiality also articulates with Identification and the Master Signifier. Identification, as the corpus notes, requires the unary trait — an element singled out from the chain — which only functions as such because the chain is differential: the trait marks a position through difference, not substance. The Master Signifier similarly quilts the chain not by possessing meaning but by occupying a differential position that anchors all others. Dialectics and Abstract are relevant anchors too: Hegel's insight that pure being is indistinguishable from pure nothing, or that abstract determination is always one-sided and must pass into its opposite, maps directly onto differentiality's claim that any term is itself only through its relation to what it is not. Differentiality thus names the logical skeleton that Žižek is arguing runs beneath all these canonical Lacanian/Hegelian concepts simultaneously.
Key formulations
Less Than Nothing: Hegel and the Shadow of Dialectical Materialism (page unknown)
Ferdinand de Saussure was the first to formulate the notion of differentiality, pointing out that the identity of a signifier resides only in a series of differences... the crucial consequence of differential identity is that the very absence of a feature can itself count as a feature, as a positive fact.
The theoretically loaded move is in the phrase "the very absence of a feature can itself count as a feature, as a positive fact": it collapses the opposition between presence and absence, making negativity structurally productive rather than merely privative — which is precisely what licenses Žižek to read Saussure, Hegel's constitutive negation, and Lacan's lack as formalizations of the same logical operation.