The book aims to pick up the logical analysis of language, as Russell conceived of it in his Principles of Mathematics, by bringing out the structural components of context-sensitivity and their fundamental, if not primitive, mathematical counterparts. Chapter 1 offers an overview of the literature and challenges the uncritical “context-unit assumption” that the semantic content of every context-sensitive expression depends on one context at a time. It then argues that any semantic content of any utterance comes from some prior content, by transposition from some context of reference to the current context. Thus, the content of the utterance depends primarily on the context-shift from which the context of utterance originates. Moreover, the linguistic meaning of an expression is understood as built up by transposition and collation of more specific contents. The ensuing picture is shown both to cover the full spread of context-sensitivity without giving up the prospect of its formal representation and to account for the connection between meaning and content without sacrificing one for the other.