Online research in philosophy

I consider Leibniz's thoughts about Hobbes's materialism, focusing on his less-discussed later thoughts about the topic. Leibniz understood Hobbes to have argued for his materialism from his imagistic theory of ideas. Leibniz offered several criticisms of this argument and the resulting materialism itself. Several of these criticisms occur in texts in which Leibniz was engaging with the generation of British philosophers after Hobbes. Of particular interest is Leibniz's correspondence with Damaris Masham. Leibniz may have been trying to communicate with Locke, but ended up discussing Masham's version of the argument for materialism that Leibniz attributed to Hobbes.

A historically persistent way of reading Leibniz regards him as some kind of conceptualist. According to this interpretation, Leibniz was either an ontological conceptualist or an epistemological conceptualist. As an ontological conceptualist, Leibniz is taken to hold the view that there exist only concepts. As an epistemological conceptualist, he is seen as believing that we think only with concepts. I argue against both conceptualist renditions. I confront the ontological conceptualist view with Leibniz’s metaphysics of creation. If the ontological conceptualist interpretation were right, then Leibniz could not invoke compossibility as a criterion of creation. But since he does invoke compossibility as a criterion of creation, the ontological conceptualist approach cannot be right. I confront the epistemological conceptualist interpretation with Leibniz’s assertion of non-conceptual content. Since Leibniz acknowledges non-conceptual content at least when it comes to metaphysical knowledge, Leibniz could not have been an epistemological conceptualist either. So, Leibniz could not have been a conceptualist at all.

This paper regards the plausibility of rejecting the scholastic claim that the “good” is a transcendental property of being—that ens et bonum convertuntur—onthe basis of two claims: (1) Stephen Cahn’s claim that evil worlds created by an evil God are intrinsically plausible—i.e., that it is plausible to think of evil as a positive and instantiable property; and (2) the claim that “evil is a primitive”—that is, that evil is a primary or basic ontological property. It argues that if an “ontological primitive” must be a property which has no basic constituents other than itself—or whose definition cannot invoke concepts or constituents other than the primitive itself—evil itself cannot be considered a primitive. Nor can it be considered a positive property.

In this paper, the author develops a theory of concepts and shows that it captures many of the ideas about concepts that Leibniz expressed in his work. Concepts are first analyzed in terms of a precise background theory of abstract objects, and once concept summation and concept containment are defined, the axioms and theorems of Leibniz's calculus of concepts (in his logical papers) are derived. This analysis of concepts is then seamlessly connected with Leibniz's modal metaphysics of complete individual concepts. The fundamental theorem of Leibniz's modal metaphysics of concepts is proved, namely, whenever an object x has F contingently, then (i) the individual concept of x contains the concept F and (ii) there is a (counterpart) complete individual concept y which doesn't contain the concept F and which `appears' at some other possible world. Finally, the author shows how the concept containment theory of truth can be made precise and made consistent with a modern conception of truth.

It is well known that Leibniz believes that the motion of bodies is caused by an internal force.1 Moreover, he distinguishes between two kinds of force that are associated with bodies, which he calls primitive and derivative forces respectively. My aim is to explain Leibniz’s account of the relation between these two kinds of force, and to address a puzzle that arises in connection with this relation. In fact Leibniz speaks of two different kinds of derivative force. The first, and most fundamental, kind of derivative force is the momentary tendency to move from one perception to another within a simple substance, or monad. Sometimes these are called “appetitions”.2 The second kind are the forces of bodies that are found in the mechanical explanations of Leibnizian Dynamics.3 We shall be concerned primarily with the latter in what follows. However, the derivative forces of monads will also play an important role in the discussion. As one might expect, Leibniz holds that derivative forces are derived from the primitive ones. This idea is more usually expressed in terms of the notion of modification. Thus, derivative forces are said to be “nothing but the modifications and results of primitive forces”4 and to “arise as shapes arise from modification of extension”.5 Here it is natural to assume that Leibniz understands the relation between primitive and derivative force in something like the way in which Descartes understood the relation between modes of extended and thinking substances and the substances themselves, namely as particular ways of being an extended or thinking thing that inhere in their subjects.6 Although this account of derivative forces as modifications of primitive forces may seem plausible at first, difficulties arise when we try to understand how it could apply to the derivative forces in Leibnizian bodies. For it seems to be in conflict with two further aspects of Leibniz’s philosophy. Both can be found in the following passage from a letter to De Volder of 1705..

If conceptual analysis is possible for finite thinkers, then there must ultimately be a distinction between complex and primitive or irreducible and unanalyzable concepts, by which complex concepts are analyzed as relations among primitive concepts. This investigation considers the advantages of categorizing intentionality as a primitive rather than analyzable concept, in both a historical Brentanian context and in terms of contemporary philosophy of mind. Arguments in support of intentionality as a primitive relation are evaluated relative to objections, especially a recent criticism by Jerry A. Fodor. Against this background, the relation between qualia and intentionality in the understanding of consciousness is explored.

Llull and Leibniz both subscribed to conceptual atomism, the belief that the majority of concepts are compounds constructed from a relatively small number of primitive concepts. Llull worked out techniques for finding the logically possible combinations of his primitives, but Leibniz criticized Llull’s execution of these techniques. This article argues that Leibniz was right about things being more complicated than Llull thought but that he was wrong about the details. The paper attempts to correct these details.

We first present an edition of the manuscript LH VII, B 2, 39 in which Leibniz develops a new formalism in order to give rigorous definitions of positive, of privative, and of primitive terms.This formalism involves a symbolic treatment of conceptual quantification which differs quite considerably from Leibniz’s “standard” theory of “indefinite concepts” as developed, e.g., in the “General Inquirles” In the subsequent commentary we give an interpretation and a critical evaluation of Leibniz’s symbolic apparatus. It turns out that the definition of privative terms and primitive terms lead to certain inconsistencies which, however, can be avoided by slight modifications.

In a recent paper, Dennis Plaisted examines an important argument that Leibniz gives for the existence of primitive concepts. After sketching a natural reading of this argument, Plaisted observes that the argument appears to imply something clearly inconsistent with Leibniz’s other views. To save Leibniz from contradiction, Plaisted offers a revision. However, his account faces a number of serious difficulties and therefore does not successfully eliminate the inconsistency. We explain these difficulties and defend a more plausible alternative. In the process, we call attention to the neglected topic of Leibniz’s views on the nature of conceiving, and reveal his commitment to the somewhat surprising thesis that one can conceive something through a concept even if one has no conscious grasp of that concept.