If one of the aims of posthumanism is to re-elaborate critically, without falling back on exceptionalist constructions, the nature of what humanity means, from its problematic inception to its uncertain, constant becoming, then Jacques Derrida’s deconstruction of what constitutes (the inscription of) a trace is highly relevant. From some of his earliest texts the French philosopher has actively sought to think of ‘meaning’ and ‘communication’ beyond the ‘sciences of language’ traditionally revolving on the notion of the linguistic sign. In the section of Of Grammatology titled ‘Linguistics and Grammatology’, devoted to a rereading of the arbitrary and differential nature of the sign as well as to the relation of inclusion between semiology and linguistics in Ferdinand de Saussure’s Course in General Linguistics, Derrida had sketched the self-deconstructing limits of Saussure’s new science of signs. Excerpting it in the chapter and quoting it more fully in the contemporaneous article on ‘The Linguistic Circle of Geneva’ as well as in the 1968 interview ‘Semiology and Grammatology’, Derrida refers to the same passage from the Course which programmatically inaugurates this new science – which (in one translation) ‘should show what constitutes signs, what laws govern them. Since the science does not yet exist, no one can say what it would be; but it has a right to existence, a place staked out in advance. Linguistics is only a part of the general science of semiology; the laws discovered by semiology will be applicable to linguistics, and the latter will circumscribe a well-defined area within the mass of anthropological facts’. While, still in ‘Linguistics and Grammatology’, Derrida proposes that ‘[b]y a substitution which would be anything but verbal, one may replace semiology by grammatology in the program of the Course in General Linguistics’, in the following chapter, ‘Of Grammatology as a Positive Science’, he unambiguously warns us that ‘[w]hat seems to announce itself now is, on the one hand, that grammatology must not be one of the sciences of man and, on the other hand, that it must not be just one regional science among others. It ought not to be one of the sciences of man, because it asks first, as its characteristic question, the question of the name of man’.
Often conceived as a hierarchical valorisation of signatum over signans (the Mediaeval Latin translations of the Stoics’ semainomenon and semainon; C. S. Peirce, Roman Jakobson), signified over signifier (Ferdinand de Saussure), signified (ideal) meaning over signifying (sensory) aspect (Edmund Husserl), the linguistic sign for Derrida partakes of a metaphysics that has maintained an essential distinction between the intelligible and the sensible. Such a reduction of the exteriority of the signifier is, in his deconstruction of the metaphysics of presence privileging speech (phonè) over writing (graphè), one form of the exclusion of writing as exterior representation. However, it is still occasionally wrongly assumed that Of Grammatology proposed a new science of writing with the ability and aim to supersede semiology and linguistics, in spite of Derrida clearly stating that ‘Of Grammatology is the title of a question: a question about the necessity of a science of writing […] but it is also a question about the limits of this science’. In producing a more generalisable concept of writing called ‘gram’ or ‘differance’, Derrida aimed to retrieve the play of differences at work in a sign never present to itself but always referring to something else, ‘constituted on the basis of the trace within it of the other elements of the chain or system’:
There are only, everywhere, differences and traces of traces. The gram, then, is the most general concept of semiology – which thus becomes grammatology – and it covers not only the field of writing in the restricted sense, but also the field of linguistics. […] The gram as différance […] is a structure and a movement no longer conceivable on the basis of the opposition presence/absence. Différance is the systematic play of differences, of the traces of differences […].
For Derrida, Saussure’s insight into the purely relational and arbitrary connection between signifier and signified implied that, since language is construed as a system of differential relations, every sign acquires its value only in relation to its difference from other signs. Every sign bears the traces of those signs from which it differs in order to receive its value as a differential sign. What was downgraded as derivative or ‘deferred presence’ in the (graphic) sign thus becomes the generalisable condition for any ‘language’ to operate; the supposed immediacy of presence is thus re-presented and a secondary effect of the trace. Writing is a sign of (or refers to) a sign only insofar as this is true of all signs. Such a differantial sign, therefore, had to be designated by another name on condition that it be likewise stripped from its metaphysical presuppositions of positive immediacy and accessibility – the trace (as the erasure) of the trace:
The erasure of the early trace (die frühe Spur) of difference is therefore the ‘same’ as its tracing in the text of metaphysics. […] The paradox of such a structure […] is an inversion of metaphysical concepts, which produces the following effect: the present becomes the sign of the sign, the trace of the trace. […] It becomes a function in a structure of generalized reference. It is a trace, and a trace of the erasure of the trace.
The trace is therefore not reducible to the sign, nor can it be turned back into one; it must be thought as the non-signifying, non-plenary difference at work in all signification, hence it is always the trace of the trace and is never purely originary. Against the ontotheological grounding of the sign caught in metaphysical conceptuality predetermining the difference between presence and absence, inside and outside – cf. the titles of the first two sub-sections of ‘Linguistics and Grammatology’: ‘The Outside and the Inside’, ‘The Outside
Is the Inside’ – the Derridean trace reintroduces a problematic of impression alongside that of expression, which is the main concern of sciences of communication based on the idea of the sign. Thus, according to Derrida’s self-deconstructing double syntax and later formula, the trace (of the trace), or trace under erasure, ‘n’arrive qu’à s’effacer’, i.e. arrives only by effacing itself / manages only to efface itself.
Whereas differences are constitutive of the sign, the trace-as-differance names the ‘prior’, ‘originary’, ‘pure’ movement without which those differences could not be conceived:
It is not the question of a constituted difference here, but rather […] of the pure movement which produces difference. The (pure) trace is differance. […] Although it does not exist, although it is never a being-present outside of all plenitude, its possibility is by rights anterior to all that one calls sign (signified/signifier, content/expression, etc.), concept or operation, motor or sensory. This differance is therefore not more sensible than intelligible and it permits the articulation of signs among themselves […].
The previous recall of Martin Heidegger’s frühe Spur (early trace), which alludes to the originary difference between Being and beings lost in the history of metaphysics, indicates that the Derridean trace did not emerge merely from an engagement with the Saussure-inherited conception of the sign in order to unsettle its traditional, reductively humanist or anthropocentric assumptions – some of its other genealogical determinations could be found in Emmanuel Levinas’s more ethical trace of the Other, or in the phenomenological (Husserlian) tradition. Rather it operates as a form of displacement and reinscription which extends the functioning of the classical concept beyond (and prior to) its reduction to a human register – in an unproblematised sense of ‘humanity’ – in order to point towards its dual non-human articulation in the animal and the technological.
The quasi-originary co-implication of the animal and the technological in this redefinition of what might constitute the ‘human’ can be located at/as the crux of the enterprise of deconstruction, including as a radical critique of anthropocentrism, anthropomorphism and liberal humanism. This accounts for the precursory relevance for posthumanism of Derrida’s sparse yet pregnant allusions in Of Grammatology to cybernetics, or ‘the entire field of control and communication theory, whether in the machine or in the animal’, when he adumbrates what would be (etymologically) a pro-gram for a generalised field of writing:
If the theory of cybernetics is by itself to oust all metaphysical concepts […] which until recently served to separate the machine from man, it must conserve the notion of writing, trace, grammè [written mark], or grapheme, until its own historico-metaphysical character is also exposed. Even before being determined as human (with all the distinctive characteristics that have always been attributed to man and the entire system of significations that they imply) or nonhuman, the grammè – or the grapheme – would thus name the element.
Instead of having recourse to the concepts that habitually serve to distinguish man from other living beings […], the notion of program is invoked. It must of course be understood in the cybernetic sense, but cybernetics is itself intelligible only in terms of a history of the possibilities of the trace […].
This succinct presentation therefore acts performatively as a ‘common core’ or ‘ground zero’ prior to the critical differentiation of the trace-as-differance ‘itself’ into its two joint axes of animality and technicity, for which the reader is referred to ‘The Animality of the Trace’ and ‘The Technicity of the Trace’.
– Shanghai Jiao Tong University, September 2020
 For this particular aspect, see ‘Signature Event Context’, in Margins of Philosophy, trans., with Additional Notes, by Alan Bass (Brighton: Harvester Press, 1982), esp. pp. 309-10.
 Jacques Derrida, Of Grammatology, corrected ed., trans. Gayatri Chakravorty Spivak (Baltimore and London: Johns Hopkins University Press, 1997), pp. 27-73.
 Derrida, Margins of Philosophy, p. 149; compare with ‘Semiology and Grammatology: Interview with Julia Kristeva’, in Positions, trans. and annotated by Alan Bass (London and New York: Continuum, 2004), pp. 15-36 (p. 23), and Of Grammatology, p. 51.
 Derrida, Of Grammatology, p. 51.
 Derrida, Of Grammatology, p. 83.
 Derrida, Positions, p. 13.
 Derrida, Positions, p. 26.
 Derrida, Positions, pp. 26-27.
 Derrida, Margins of Philosophy, p. 9.
 Geoffrey Bennington, ‘Saussure and Derrida’, in The Cambridge Companion to Saussure, ed. Carol Sanders (Cambridge: Cambridge University Press, 2004), p. 193.
 Derrida, Of Grammatology, p. 43; cf. also p. 29.
 Derrida, Margins of Philosophy, p. 24; cf. also Of Grammatology, p. 61 on the originary (non)trace as origin of the origin, as well as Rodolphe Gasché, The Tain of the Mirror: Derrida and the Philosophy of Reflection (Cambridge, MA and London: Harvard University Press, 1986), pp. 186-205 (‘The Infrastructure as Arche-Trace’, ‘The Infrastructure as Difference’), pp. 289-92 (‘A System of Traces’).
 Cf. Derrida, Positions, p. 29: grammatology ‘would be a nonexpressive semiology only on the condition of transforming the concept of sign and of uprooting it from its congenital expressivism’.
 Derrida, Cinders / Feu la cendre, trans. Ned Lukacher (Lincoln, NE and London: University of Nebraska Press, 1991), passim, and ‘How to Avoid Speaking: Denials’, trans. Ken Frieden and Elizabeth Rottenberg, in Psyche: Inventions of the Other, Volume II, ed. Peggy Kamuf and Elizabeth Rottenberg (Stanford: Stanford University Press, 2008), p. 166.
 Derrida, Of Grammatology, p. 62.
 Derrida mentions Levinas’s ‘La Trace de l’autre’ in ‘Violence and Metaphysics’, in Writing and Difference, trans., with an introduction and additional notes, by Alan Bass (London: Routledge and Kegan Paul, 1978), pp. 118, 396, n. 1 (which refers to its concomitant publication), 412, n. 92 (which quotes from it). See also Robert Bernasconi, ‘The Trace of Levinas in Derrida’, in Derrida and Différance, ed. David Wood and Robert Bernasconi (Evanston, IL: Northwestern University Press, 1989), pp. 13-29.
 See especially Jacques Derrida et al., Edmund Husserl’s ‘Origin of Geometry’: An Introduction, new ed., trans., with preface and afterword, by John P. Leavey, Jr. (Lincoln, NE: University of Nebraska Press, 1989), and, for a critical articulation, Paola Marrati, Genesis and Trace: Derrida Reading Husserl and Heidegger, trans. Simon Sparks (Stanford: Stanford University Press, 2005).
 Norbert Wiener, Cybernetics, or Control and Communication in the Animal and the Machine, 2nd ed. (Cambridge, MA: The M. I. T. Press, 1948), p. 11.
 Derrida, Of Grammatology, p. 9.
 Derrida, Of Grammatology, p. 84.