The term “sentiment” marks the recognition that emotions are social and historical. We tend to think of feelings as personal and interior—yet it is often easy to see that they are structured and shared. “Sentiment,” “sentimental,” and “sentimentality” are used at moments when the entanglement of the subjective and the public is explicitly acknowledged or (often) invoked and obscured. They are vexed and value-laden terms, which have a complex range of uses in everyday speech and have been the focus of much debate in literary history, American studies, and cultural studies. The clearest common element of definitions and discussions of “sentiment” is that it is linked to emotion or affect. When we are moved, the experience is anchored in our bodies. Tears may come to our eyes, and our hearts may beat faster; perhaps our stomach roils or our skin flushes. These physiological responses are emotion’s most intimate aspects and at the same time its least individual, because they are common to all humans and in some cases can be observed in other animals. But scholars across many disciplines argue that sensations become emotions only through language and memory as they are played out in the theater of the brain;...