"The Science of the Individual: Leibniz's Ontology of Individual Substance" offers an in-depth analysis of Leibniz's concept of individual substance, which serves as the foundation of his metaphysical considerations. This work highlights the connection to a long philosophical tradition while also addressing the breaks with conventional views on the individual. Leibniz's reflections are not merely the result of traditional logical structures but arise from an unbiased examination of our ontological framework. The interactions between truth, linguistic analysis, and the phenomenological experience of the mind are explored in detail. The book sheds light on the challenges Leibniz faced during a time of significant paradigm shifts and offers new perspectives on central themes of his philosophy, such as individual identity and the essentiality of all properties of an individual. This comprehensive study is of great interest to both students and professionals in philosophy.