The relationship between emotion and language, understood as verbal communication, is both crucial and problematic for historians of emotions. Crucial because written language is for historians the main gateway into past emotions, although by all means not the only one available; problematic because language not only expresses or reflects emotion, but provokes, shapes, simulates, and dissimulates it. Indeed a precise awareness of the power of language over the emotions is the very foundation of the art of rhetoric in the West. Charles Darwin, however, looked not to verbal communication but to facial expressions to find what he called “the language of the emotions.” Throughout The Expression of Emotions (1872) he attempted to find “the innate and universal” signs, common to man and animals,4 that could function as guides to the expression of emotion as opposed to language, which he considered an “artificial,” learned habit. The conventional nature of language and its cultural specificity, indeed, appear to many the ultimate opaque barrier to the historical study of emotions, especially if one understands the latter, commonsensically, as bodily, universal, and nonrational.
Yet, anthropologists first, and historians more recently have resorted to the collection of emotion-words as a privileged tool to describe in a holistic way the emotional categories of the communities they studied. The historian of medieval linguistics Irene Rosier has written interestingly on the way medieval grammarians conceived of interjections in speech. Metaphors, it has been noted, are often used to verbalise emotion. It is also increasingly accepted that the process of understanding metaphors interacts with emotional experience. Far from being mere rhetorical embellishment, metaphor is now recognised as playing a fundamental cognitive role. Two linguists, Lakoff and Johnson, advanced the theory in a book of 1980, that basic metaphors, often derived from bodily experience, are deeply ingrained in all languages (for example “anger is hot” and “anger is like a fluid”). Students of communication theory have suggested that metaphorical language is, under certain conditions, more persuasive than literal language.