Ontological Soufflé

Possibilities are so much easier to swallow. So transform those left‐over cosmological arguments into scrumptious new ontological arguments.     

German Idealism and the Concept of Punishment

This paper examines the Leibnizian background to Kant's critique of the ontological argument. I present Kant's claim that existence is not a real predicate, already formulated in his pre-critical essay of 1673, as a generalization of Leibniz's reasoning regarding the existence of created things. The first section studies Leibniz's equivocations on the notion of existence and shows that he employs two distinct notions of existence – one for God and another for created substances. The second section examines Kant's position in his early paper of 1763. My claim is that Kant's view of existence in 1763, namely that it is not a predicate, is strongly related to the logical notion of possibility, formulated by Leibniz and accepted by Kant.     

Idealism and the Ontological Argument

The ontological proof became something of a signature argument for the British Idealist movement and this paper examines how and why that was so. Beginning with an account of Hegel's understanding of the argument, it looks at how the thesis was picked up, developed and criticized by the Cairds, Bradley, Pringle-Pattison and others. The importance of Bradley's reading in particular is stressed. Lastly, consideration is given to Collingwood's lifelong interest in the proof and it is argued that his attention is best understood as a direct continuation of theirs. In view of the fact that recent commentators have tried to draw a sharp line between Collingwood's approach to metaphysics and ontology and that of his predecessors, the establishment of this connection calls for a measure of reassessment on both sides.     

Explaining and Explaining Away in Cosmology and Theology

Modern cosmology raises two significant questions that potentially relate to theology: does the universe have a beginning, and why is the universe so apparently fine tuned for life? In a significant paper, Mark McCartney and David Glass ask whether science can explain away, or at least explain away in part, such features of the universe in cosmology and other sciences that may alternatively invite a theological explanation. In this paper I argue that two proposals made by cosmologists fail to explain away the universe's beginning, and that science is powerless to explain away the more fundamental question as to why there is a universe at all. I argue similarly that scientific, or quasi-scientific, proposals such as the multiverse fail to explain away the fine tuning.     

The Relation between Formal and Informal Logic

The issue of the relationship between formal and informal logic depends strongly on how one understands these two designations. While there is very little disagreement about the nature of formal logic, the same is not true regarding informal logic, which is understood in various (often incompatible) ways by various thinkers. After reviewing some of the more prominent conceptions of informal logic, I will present my own, defend it and then show how informal logic, so understood, is complementary to formal logic.     

Logical Argument Structures in Decision-making

Perelman and Olbrechts-Tyteca's practical reasoning theory has attracted a great deal of interest since its publication in 1969. Their most important assertion, however, that argument is the logical basis for practical decision-making, has been under-utilized, primarily because it was not sufficiently operationalized for research purposes. This essay presents an operationalization of practical reasoning for use in analyzing argument logics that emerge through group interaction. Particular elements of discourse and argument are identified as responding to principles put forward by Perelman and Olbrechts-Tyteca, and are viewed as fitting together in a kind of logical argument structure that is well suited to the study of practical arguments in decision-making. Both the content elements and the logical argument structure are illustrated using examples from two studies examining decision logics in public participation and jury decision-making. Advantages of this approach and proposed recognition of a new `filtered' type of argument structure are discussed.     

Six types of fallaciousness: Toward a realistic theory of logical criticism

I begin by formulating the problem of the nature of fallacy in terms of the logic of the negative evaluation of argument, that is, in terms of a theory of logical criticism; here I discuss several features of my approach and several advantages vis-à-vis other approaches; a main feature of my approach is the concern to avoid both formalist and empiricist excesses. I then define six types of fallaciousness, labeled formal, explanatory, presuppositional, positive, semantical, and persuasive; they all involve arguments whose conclusion may be said not to follow from the premises, that is, they involve the logical evaluation of relationships among propositions. I also provide a set of data consisting of four historical cases or nine specific instances of fallacious arguments; these all pertain to the Copernican controversy about the earth's motion in the seventeenth century. I end with a discussion of further problems and inquiries that deserve attention.     

More on Putnam’s models: a reply to Belloti

In an earlier paper, I claimed that one version of Putnam's model-theoretic argument against realism turned on a subtle, but philosophically significant, mathematical mistake. Recently, Luca Bellotti has criticized my argument for this claim. This paper responds to Bellotti's criticisms.     

Resolving arguments accurately

This empirical investigation examined how ordinary language users resolved disagreements over the solutions to categorical syllogisms. Forty-six participants completed puzzles in logic. After completing the puzzles, participants were then randomly paired into 23 to compare their answers and to resolve 159 disagreements. Results indicate that the most frequently used strategies for resolving disagreements centered on: (a) arguing over the merits of the position (47% of the time) and (b) appealing to past solutions as a means of addressing current disputes (28% of the time). In addition, the data revealed that the most frequently used strategy (arguing the merits of the positions) was no more effective than random choice (52% increase in correct solutions) while the strategy of appealing to past solutions significantly aided dyads in reaching correct solutions (70% increase in correct solutions).     

Free-Variable Tableaux for Propositional Modal Logics

Free-variable semantic tableaux are a well-established technique for first-order theorem proving where free variables act as a meta-linguistic device for tracking the eigenvariables used during proof search. We present the theoretical foundations to extend this technique to propositional modal logics, including non-trivial rigorous proofs of soundness and completeness, and also present various techniques that improve the efficiency of the basic naive method for such tableaux.     

Dynamical agents: Consciousness, causation, and two specters of epiphenomenalism

The aim of this paper is to defend the causal efficacy of consciousness against two specters of epiphenomenalism. We argue that these challenges are best met, on the one hand, by rejecting all forms of consciousness-body dualism, and on the other, by adopting a dynamical systems approach to understanding the causal efficacy of conscious experience. We argue that this non-reductive identity theory provides the theoretical resources for reconciling the reality and efficacy of consciousness with the neurophysiology of the brain and body.

Connection Tableau Calculi with Disjunctive Constraints

Automated theorem proving amounts to solving search problems in usually tremendous search spaces. A lot of research therefore focuses on search space reductions. Our approach reduces the search space which arises when using so-called connection tableau calculi for first-order automated theorem proving. It uses disjunctive constraints over first-order equations to compress certain parts of this search space. We present the basics of our constrained-connection-tableau calculi, a constraint extension of connection tableau calculi, and deal with the efficient handling of constraints during the search process. The new techniques are integrated into the automated connection tableau prover Setheo.     

Hilbert's epsilon as an operator of indefinite committed choice

Hilbert and Bernays avoided overspecification of Hilbert's ε-operator. They axiomatized only what was relevant for their proof-theoretic investigations. Semantically, this left the ε-operator underspecified. After briefly reviewing the literature on semantics of Hilbert's epsilon operator, we propose a new semantics with the following features: We avoid overspecification (such as right-uniqueness), but admit indefinite choice, committed choice, and classical logics. Moreover, our semantics for the ε simplifies proof search and is natural in the sense that it mirrors some cases of referential interpretation of indefinite articles in natural language.     

A New Representation Theorem for Contranegative Deontic Logic

The logic of an ought operator O is contranegative with respect to an underlying preference relation if it satisfies the property Op & (¬p)(¬q) Oq. Here the condition that is interpolative ((p (pq) q) (q (pq) p)) is shown to be necessary and sufficient for all -contranegative preference relations to satisfy the plausible deontic postulates agglomeration (Op & OqO(p&q)) and disjunctive division (O(p&q) Op Oq).