This volume is unusually important because it contains for the first time a complete translation of Jean-Jacques Rousseau's botanical writings and a thorough, indeed excellent set of notes. The translation and the notes are the work of Alexandra Cook; she also co-wrote the volume's Introduction with Christopher Kelly. Rousseau has long been known to scholars as a philosopher of nature. Cook's work allows us to see for ourselves what Jean-Jacques actually knew about one great sphere of nature, i.e. plants and their metamorphosis (Geothe takes his term and his theory from Rousseau's inspiration). Rousseau was one of the fathers of field botany, a champion of Linnean terminology but also of the natural system of classification formulated by the Jussieus. Cook's will legitimately be the definitive translation for many years to come; her translation is an important event. I await her monograph on the subject.