  In this paper we explore the relationships between Calvino's memos and
Mathematics. In the first part, we discuss how Lightness, Quickness,
Exactitude, Visibility, Multiplicity are present in the mathematical language,
reasoning and in the work of the mathematician. In addiction, we follow a
similar path for the topics of Calvino's lecture of which we only know the
title or some notes. In the final part, we explain why `Singularity' could be
chosen as topic for Calvino's seventh lecture.
