"No thing is complete in itself, and it can only be completed by what it lacks. But what each particular thing lacks is infinite; we cannot know in advance what complement it calls for. . . the essential, generative mother-difference, had been found. . . A difference: the cause is radically that. . .The primal insemination is dissemination. A trace, a graft whose traces have been lost. Whether in the case of what is called 'language' or in the case of some "real" seed-sowing, each term is indeed a germ, and each germ a term. The term, the atomic element, engenders by division, grafting, proliferation. . . It would be possible to reconstruct the network . . . by references to all kinds of atomistic theories, which are also theories of sperm (Dissemination 304)."
Differance constitutes the brunt of Derrida's attack on logocentrism. It shows that the Western philosophical tradition futilely exaggerates difference in the attempt to undermine trace. To repeat, logocentrism vaunts ideals such as self-presence, center, and positive origins in meaning. However Derrida contends that these ideals cannot exist without being supplemented--more precisely compensated--by opposing categories like difference, absence, and repetition. Returning to the traditional speech/writing opposition, speech has been thought to be the single medium through which entirely "self-present" meaning can be communicated. The listener is allegedly put into direct contact with the speaker's originally intended meaning. In writing, meaning is only represented. . . the context and the writer's intentions are remote from us, replicated in degraded form.
Derrida objects to this naive construction, saying that the qualities completely attributed to each term in fact blend into one another. He moves to point out that the work of substitution is prerequisite for anything to be deemed "original." The fact that writing is said to supplement speech through its substitution presupposes an always-existing lack, or absence in speech. Writing acts as a prosthesis for handicaps already evident in speech. Not everyone can be in attendance to hear a speaker's pontifications, but people may wish to know what was said anyhow. Writing in fact strives to compensate for the reader/listener's absence at the moment of utterance. There is also the absence threatened by loss of memory, which writing ameliorates. Writing thus combats absence by hardening it into something that would endure the ravages of time, hence waging war against speech's transience. Speech therefore cannot be present everywhere--neither in space nor in time. These handicaps suspiciously seem to contradict the very qualities which speech claims to embody in pure form. Likewise, writing is used to remedy the ills that it is said to contain.
How then, is speech accepted as an originary, thus incorruptibly self-present practice? And how is writing used to validate this assumption? Once again, it is through substitution. Just as speech cannot everywhere be present to listeners, by the same token writing cannot be present to the writer. Texts can reside in a considerable amount of distance from its creator. The more that writing substitutes for the "original" thought or utterance, the more it instills the sense of distance from that objective origin when the expression was fully present to the author's consciousness. The more that "self-present" speech reproduces and disperses itself in the form of writing, thus creating differance, the more it pretends to threaten its own absence. Quite paradoxically, through the dissemination of substitutes, the order of origin and self-present meaning are increasingly privileged. The time has come to propose a different question: if origin is so dependent on substitutes to be original, to be everywhere present, why is it that origin is identified with absolutely self-present, centered meaning? It is not that there is no such thing as an originating thought or utterance. It is that this originary gesture is shot through with the very qualities that it is supposed to oppose. It is not that speech equals presence and writing equals absence. It is that speech and writing fill each other's absence. At the very heart of it, they are two counter--stabilizing mechanisms in the general domain of language.