Leibniz: Determinist, Theist, Idealist

Leibniz: Determinist, Theist, Idealist

Leibniz: Determinist, Theist, Idealist

Leibniz: Determinist, Theist, Idealist


Legendary since his own time as a universal genius, Gottfried Wilhelm Leibniz (1646-1716) contributed significantly to almost every branch of learning. One of the creators of modern mathematics, and probably the most sophisticated logician between the Middle Ages and Frege, as well as a pioneer of ecumenical theology, he also wrote extensively on such diverse subjects as history, geology, and physics. But the part of his work that is most studied today is probably his writings in metaphysics, which have been the focus of particularly lively philosophical discussion in the last twenty years or so. The writings contain one of the great classic systems of modern philosophy, but the system must be pieced together from a vast and miscellaneous array of manuscripts, letters, articles, and books, in a way that makes especially strenuous demands on scholarship. This book presents an in-depth interpretation of three important parts of Leibniz's metaphysics, thoroughly grounded in the texts as well as in philosophical analysis and critique. The three areas discussed are the metaphysical part of Leibniz's philosophy of logic, his essentially theological treatment of the central issues of ontology, and his theory of substance (the famous theory of monads).


Among the theses that Leibniz sent to Antoine Arnauld in February 1686, the one that aroused Arnauld's initial objection was the following statement:

Since the individual concept of each person contains once for all everything that will ever happen to him, one sees in it the proofs a priori or reasons for the truth of each event, or why one has occurred rather than another. (LA 12)

All the predicates of an individual substance are contained in the concept of that individual, according to Leibniz. This thesis gives rise to many questions about the relation of individuals to their predicates. Why should the predicates be contained in the concept of the individual, and not just in the individual itself? Why does Leibniz infer from the conceptual containment thesis, as he does (DM 14), that all the states of an individual substance are caused by previous states of that individual alone? We will come to these questions, in the course of this chapter and the next, but the present investigation is organized around another issue. It is an issue of counterfactual identity; Arnauld raised it in these words:

Since it is impossible that I should not always have remained myself, whether I had married or lived in celibacy, the individual concept of myself contained neither of these two states; just as it is well to infer: this block of marble is the same whether it be at rest or be moved; therefore neither rest nor motion is contained in its individual concept. (LA 30)

Arnauld affirms transworld or counterfactual identity as a reason for rejecting Leibniz's conceptual containment thesis. He denies that his actual predicate of lifelong celibacy is contained in his individual concept, on the ground that he is the same individual as one who would, under some possible circumstances, have married. In his response, as in a number of other places in his writings, Leibniz made clear that he did not accept Arnauld's assumption of counterfactual identity. He held that no actual individual creature would have existed if anything at all had gone differently from the way things go in the actual world-- that if Arnauld, for example, had married, he would not have been Arnauld [or more precisely, that anyone who got married would not have been Arnauld (cf.

Search by... Author
Show... All Results Primary Sources Peer-reviewed


An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.