A Treatise of the Laws of Nature, originallytitled De Legibus Naturae, first appeared in 1672as a theoretical response to a range of issues that cametogether during the late 1660s. It conveyed a convictionthat science might offer an effective means ofdemonstrating both the contents and the obligatoryforce of the law of nature. At a time when Hobbesswork appeared to suggest that the application ofscience undermined rather than supported the idea ofobligatory natural law, Cumberlands De LegibusNaturae provided a scientific explanation of the naturalnecessity of altruism.Through his argument for a moral obligation tonatural law, Cumberland made a critical intervention inthe early debate over the role of natural jurisprudenceat a moment when the natural law project was widelysuspected of heterodoxy and incoherence.Liberty Fund publishes the first modern edition of ATreatise of the Laws of Nature, based on JohnMaxwells English translation of 1727. The editionincludes Maxwells extensive notes and appendixes. Italso provides, for the first time in English, manuscriptadditions by Cumberland and material from Barbeyracs1744 French edition and John Towerss edition of1750.Richard Cumberland(16321718) was bishop ofPeterborough.Jon Parkin is a Lecturer in Politicsat the University of York, United Kingdom.Knud Haakonssen is Professor of Intellectual History and Director of the Centre for Intellectual History at the University of Sussex, England.