Jacques Derrida has put the issue of the pharmakos front and center in the question of "reversed predications." Between something posited and its opposite, there is a gap. This gap cannot be filled by the classic device of coincidentia oppositorum but must be "kept open and dynamic." According to Derrida (Dissemination, 1981, p. 103), the pharmakon of writing itself cannot be reduced to the series of oppositional concepts that it precedes and produces. Peter Mahon (University of British Columbia): “If the pharmakon is ‘ambivalent,’ it is because it constitutes the medium in which opposites are opposed, the movement and the play that links them among themselves, reverses them or makes one side cross over into the other (soul/ body, good/ evil, inside/ outside, memory/ forgetfulness, speech/ writing, etc.) .…The pharmakon is the movement, the locus, and the play: (the production of) difference. It is the différance of difference. It holds in reserve, in its undecided shadow and vigil, the opposites and the differends that the process of discrimination will come to carve out. Contradictions and pairs of opposites are lifted from the bottom of this diacritical, differing, deferring, reserve. Already inhabited by différance, this reserve, even though it ‘precedes’ the opposition between different effects, even though it preexists differences as effects, does not have the punctual simplicity of a coincidentia oppositorum. It is from this fund that dialectics draws its reserves” (Dissemination, p. 127).