Chapter “Introduction” introduces the book’s structure, main arguments and conclusions. It exposes the unwarranted absence of Sade’s metaphysics from the secondary literature, despite that his texts abound with philosophical dialogue and speculation. It provides evidence that Sade’s opus has been misconstrued as primarily invested in psychology, politics, polemic, or as symptoms of personal libertinism, and argues to the contrary that his metaphysical commitments are as central as they are distinctive and innovative. It posits the need to redress this misinterpretation and assesses the challenges involved in constructing a cogent philosophical system from a literary opus rich in irony and marred by inconsistencies.