This article proposes a semiotic theory of social imaginaries. Drawing on the work of Umberto Eco, Reinhart Koselleck and Martin Heidegger, it shows the logic that governs the relationship between temporality and semiosis, sign and its constant reinterpretation. In this sense, this work can be read as a sort of epistemological program that also represents the background on which the various contributors to this Special Issue have developed their analyses and narratives.