Imagination in literary imitation

The trace of reality in literary imitation is perceived in the act of writing that expresses the ability of the author to create a fictional world. In this regard، imagination is here sought، is worth exploring. In this respect، the methodology used to construct this imaginary، often uses some fragments present in reality. Hence the question of the trace of the latter that occurs in literature، such imitation. Track within the meaning of Pierce، back to the idea of index fingerprint. But what is the boundary between the natural object «real» and that imitation is the trace?