Communication of perceptual experiences by means of a linguistic description constitutes one of the main functions of language. Therefore the processes and the mechanisms that relate perception and language are basic to our cognitive system. When we consider the border zone between perception and language, or when we study how the two modalities function as they interact, and which processes operate in such interaction, we must establish which of them takes the lead. Is it the principles governing visual perception that determine what will be transferred into the linguistic description or is it the rules of categorization and linguistic production that structure and select what will be said about what was perceived? Philosophers of language have preferred the latter view when they make reference to truth conditions in explaining the logical foundations of the propositions of a natural language. On the other hand they suggest that truth conditions are connected to the perception of reality.¹ Nevertheless few of them are willing to tackle the difficult task of identifying the characteristics of such a connection.²