Wonder has been celebrated as the quintessential passion of childhood. From the earliest stages of our intellectual history, it has been acclaimed as the driving force of inquiry and the prime passion of thought. Yet for an emotion acknowledged so widely for the multiple roles it plays in our lives, wonder has led a singularly shadowy existence in recent reflections. Philosophers have largely passed it over in silence; emotion theorists have shunned it as a case that sits awkwardly within their analytical frameworks. So what is wonder, and why does it matter? In this book, Sophia Vasalou sketches a "grammar" of wonder that pursues the complexities of wonder as an emotional experience that has carved colorful tracks through our language and our intellectual history, not only in philosophy and science but also in art and religious experience. A richer grammar of wonder and broader window into its past can give us the tools we need for thinking more insightfully about wonder, and for reflecting on the place it should occupy within our emotional lives.