Our communication is limitedby misunderstanding. Rhetoric, as Professor Richards defines it, is the study of misunderstanding and its remedies. The conventional rules of the old rhetoric and the formulations of scientific language have narrow application to conversational speech; Professor Richard's definition of rhetoric is based on a practical question: how do words work in discourse? To answer this question, he examines the interaction of words with each other and with their contexts, showing how a continual synthesis of meaning, or "principle of metaphor", gives life to discussion. It is through comprehension of the way meaning changes in discourse that we can better control and animate our use of words, and so decrease misunderstanding.