There is a close connection in Gottfried Wilhelm Leibniz’s mind between the notions of self and substance. R. W. Meyer, in his classic 1948 text, Leibnitz and the Seventeenth-Century Revolution, writes that “the monad ... is nothing but a 1 représentation (in both senses of the French word) of Leibniz’s personality in metaphysical symbols; and there was, under contemporary circumstances, no need 2 to ‘introduce’ this concept apart from ‘propounding’ it. ” It is not clear what Meyer means here except that from the consideration of his own self, in some way Leibniz comes to his concept of simple substance, or monad. Herbert Carr, in an even earlier work, notes that Leibniz held that “the only real unities in nature are formal, not material. ... [and] [f]or a long time Leibniz was content to call the formal unities or substantial forms he was speaking about, souls. This had the advantage that it referred at once to the fact of experience which supplies the very 3 type of a substantial form, the self or ego. ” Finally, Nicholas Rescher, in his usual forthright manner, states that “[i]n all of Leibniz’s expositions of his philosophy, 4 the human person is the paradigm of a substance.

Locke and Leibniz on Substance gathers together papers by an international group of academic experts, examining the metaphysical concept of substance in the writings of these two towering philosophers of the early modern period. Each of these newly-commissioned essays considers important interpretative issues concerning the role that the notion of substance plays in the work of Locke and Leibniz, and its intersection with other key issues, such as personal identity. Contributors also consider the relationship between the two philosophers and contemporaries such as Descartes and Hume.

The Monadology (French: La Monadologie, 1714) is one of Gottfried Leibniz's best known works representing his later philosophy. It is a short text which sketches in some 90 paragraphs a metaphysics of simple substances, or monads. In it, he offers a new solution to mind and matter interaction by means of a pre-established harmony expressed as the 'Best of all possible worlds' form of optimism.

Christia Mercer analyses Leibniz's early works, demonstrating that the metaphysics of pre-established harmony developed many years earlier than previously believed. A much deeper understanding of some of Leibniz's key doctrines emerges, which will prompt scholars to reconsider their basic assumptions about early modern philosophy and science.

The revival of Leibniz studies in the past twenty-five years has cast important new light on both the context and content of Leibniz's philosophical thought. Where earlier English-language scholarship understood Leibniz's philosophy as issuing from his preoccupations with logic and language, recent work has recommended an account on which theological, ethical, and metaphysical themes figure centrally in Leibniz's thought throughout his career. The significance of these themes to the development of Leibniz's philosophy is the subject of increasing attention by philosophers and historians. This collection of new essays by a distinguished group of scholars offers an up-to-date overview of the current state of Leibniz research. In focusing on nature and freedom, the volume revisits two key topics in Leibniz's thought, on which he engaged both contemporary and historical arguments. Important contributions to Leibniz scholarship in their own right, these articles collectively provide readers a framework in which to better situate Leibniz's distinctive philosophy of nature and the congenial home for a morally significant freedom that he took it to provide.