The end result of the meeting between Freud’s thing presentation and word presentation is a sign that has a relation to speech that is similar to a pictorial or a hieroglyphic sign; something needs to be decoded, interpretation is dependent on context and the thing itself is always one step removed, impossible to formulate without something supplementary. In this sense, the traumatic representation cannot be spoken, but is nevertheless something that has been inscribed, the there-then inherent in the here-now. It has made an impression, but one which has never been conscious, never been subject to experience, but is, rather, a fresh registration. For Derrida these two hypotheses; the functional and the topographical can be combined in a writing machine combining “freshness of surface and depth of retention” (Derrida, 1978: 217). This “two-handed” (1978: 226) machine is best exemplified by Freud’s wax writing tablet from his 1925 paper, ‘A Note Upon the “Mystic Writing Pad”’. The way memories operate can be supplemented through mark-making, Freud says; a note made in pen in a notebook, say—laying down a permanent trace—or they can be erased to make room for further marks, as a chalkboard, for example, can. They cannot do both. The pad, a child’s toy, known often as a magic slate, allows the marks on the pad to be erased, while retaining a permanent trace. This is effected through the lifting of a celluloid covering sheet from the wax lower level, which as well as causing the traces to disappear, allow earlier traces to be made out on the wax surface (see Freud, 1925 [1924]). The metaphor of the writing pad allows Derrida to imagine the sort of machine that might describe a writing that represents psychical content, to show that “we are written as we write” (1978: 226). For Derrida the trace acts as an “erasure of selfhood”, the erasure of a self that is in anguish about its own disappearance (1978: 230); a trace, too, of the obscene emptiness of trauma.
So to pause for a moment and return to our alternative question: how is trauma represented? I’ve suggested that trauma is represented in a relation to absence; trauma is represented in traces; trauma has specific relations to temporality and deferral, to exteriority and interiority. And that these relations and representations can be thought about in terms of the index, and its particular concerns with deferral, absence and inscription.