This book offers a comprehensive treatment of the philosophical system of the seventeenth-century philosopher Pierre Gassendi. Gassendi's importance is widely recognized and is essential for understanding early modern philosophers and scientists such as Locke, Leibniz and Newton. Offering a systematic overview of his contributions, LoLordo situates Gassendi's views within the context of sixteenth- and early seventeenth-century natural philosophy as represented by a variety of intellectual traditions, including scholastic Aristotelianism, Renaissance Neo-Platonism, and the emerging mechanical philosophy. LoLordo's work will be essential reading for historians of early modern philosophy and science.