This thesis discusses four philosophical themes in Gille Deleuze’s The Fold: Leibniz and the Baroque: perception, matter, the body, and the world . The first chapter introduces Deleuze’s interpretation of Leibniz’s Monadology, which implies a a particular view of the relation between subject and object. As such, this brings about a peculiar view of perception. Based on this peculiar view of perception, the second chapter elucidates a special notion of matter, i.e. matter is not an object external to the consciousness, instead necessarily a transitional layer in Deleuze’s interpretation of Leibniz’s Monadology. In the third chapter, it deal with the idea of body, which is constituted by the notion of perception and matter in Monadology. it also explores the constitutive conditions of the notion of body. In the fourth chapter, it will elaborate the concept of the world, i.e. the limitation of the concept of perception.