In this paper we investigate possible links between historical linguistics and cognitive science, or theory of the mind. Our primary goal is to demonstrate that historically documented processes of a certain type, i.e. those relating to semantic change and grammaticalization, form a unified theoretical bundle which gives insight into the cognitive processes at work in language organization and evolution. We reject the notion that historical phenomena are excluded from cognitive speculation on the grounds that they are untestable. Rather, we argue for an extension of Labov’s uniformitarian doctrine, which states “that the same mechanisms which operated to produce the large-scale changes of the past may be observed operating in the current ch...