Robert Boyle (1627–91), one of the most prominent natural philosophers of the second half of the seventeenth century, wrote voluminously on chemistry, the philosophy of nature, theology and religion. Michael Hunter, whose editions of Boyle's works and correspondence are central to the recent upsurge of scholarship on Boyle, has now produced a detailed biography of him based on his intimate knowledge of and immersion in Boyle's manuscripts and correspondence. The biography traces Boyle's life from his birth into a wealthy Anglo-Irish family, to his education, his five-year grand tour of continental Europe, to his scholarly, philanthropic and financial activities in England and Ireland. Hunter provides numerous details about Boyle's family, his encounters with other people, and the circumstances in which he wrote his numerous books and articles. Significantly, he maps out the development of Boyle's thinking. Boyle's early writings focused on morality and piety. Around 1650 his contact with the American alchemist George Starkey, who had settled in London, stimulated his interest in chemistry and alchemy, leading to a lifelong devotion to ‘experimental philosophy’ as well as the mechanical philosophy of nature. Boyle's most famous result was the discovery of the inverse relationship between the pressure and volume of air. He communicated regularly with a wide circle of people, including most of the important natural philosophers both in England and on the continent. Boyle wrote extensively about the close relationship between natural philosophy and theology, stressing mutual reinforcement rather than conflict. In a number of books he argued that the study of nature amounts to an act of worship as it acquaints the natural philosopher with God's wisdom, power and goodness. Conversely, he saw religious belief as a motive for the study of nature. Hunter's biography leads the reader through the intricacies of Boyle's connections – social, philosophical and theological. His account rests heavily on his own detailed knowledge of Boyle's publications and manuscripts. This book will provide essential background for scholars embarking on more conceptual studies of Boyle's place in early modern thought.