So far we have considered distinction primarily as an act taking place. But once a distinction has been accomplished and we want to deal with it again, it is available to us differently — through the trace it has left.
Act and trace can therefore be understood as two modes of distinction. An act is distinction as it takes place. A trace is a distinction in the mode of access to an already accomplished act. A trace is not outside the world or a copy of a distinction in some separate space: it enters further movement as a new present determination.
In this sense, almost everything we can presently work with consists of traces of distinctions. Signs, memory states, records, objects, relations, and formal expressions differ in their organization, but can perform the same role: retain an accomplished distinction and make it available to further distinction.
An important consequence follows from the nature of a trace as a distinction in the mode of access: while the distinction being accessed is preserved, the mode of access itself — and therefore the trace — can be replaced. This is the interchangeability of traces. The same distinction can be retained through different traces, while the same carrier can become a trace of different distinctions depending on the relations into which it enters. What matters for further movement is not the material of the trace in itself, but the distinction to which it provides access.
This gives rise to the first hint of the incompleteness of systems of traces. A trace provides access to a distinction, but does not coincide with the act that accomplished it. Any system working only with traces therefore deals not with the fullness of distinction taking place, but with an already retained form of access to it. Incompleteness here is not an accidental defect of representation, but a consequence of the transition from act to trace itself.
This sets a boundary of formalization. A formal system can store, transform, and connect traces, but by its nature the act of a new distinction arising is not given to it as a formal object: as soon as we make that act accessible to formal work, we are already dealing with its trace.
