The “aphoristic form causes difficulty,” Nietzsche lamented in 1887, for “today this form is not taken seriously enough.” Over a century later, Nietzsche’s Aphoristic Challenge offers the first book-length study in English devoted explicitly to Nietzsche’s aphoristic writings, including Human, All Too Human and The Gay Science. The study argues that the function of the aphorism for Nietzsche changes, but can best be understood in terms of excess.