Online research in philosophy

Mental probability logic is a psychological competence theory about how humans interpret and reason about common-sense conditionals. Probability logic is proposed as an appropriate standard of reference for evaluating the rationality of human inferences. Common-sense conditionals are interpreted as “high” conditional probabilities, P(B|A) > .5. Probability logical accounts of nonmonotonic reasoning and inference rules like the modus ponens are explored. Categorical syllogisms with comparative and quantitative quantifiers are investigated. A series of eight experiments on human probabilistic reasoning in the framework of the basic nonmonotonic system p corroborate the psychological plausibility of the proposed approach.

Recent evidence suggests that performance on reasoning tasks may reflect the operation of a number of distinct cognitive mechanisms and processes. This paper explores the implications of this view of the mind for the descriptive and normative assessment of reasoning. I suggest that descriptive questions such as “Are we equipped to reason using rule X?” and normative questions such as “Are we rational?” are obsolete—they do not possess a fine enough grain of architectural resolution to accurately characterize the mind. I explore how this general lesson can apply to specific experimental interpretations, and suggest that 'rationality' must be evaluated along a number of importantly distinct dimensions.

Over the past few decades, reasoning and rationality have been the focus of enormous interdisciplinary attention, attracting interest from philosophers, psychologists, economists, statisticians and anthropologists, among others. The widespread interest in the topic reflects the central status of reasoning in human affairs. But it also suggests that there are many different though related projects and tasks which need to be addressed if we are to attain a comprehensive understanding of reasoning.

"Objectivity" and "rationality" of science do not depend on freedom from all "presuppositions", but are inextricably bound with the employment of background beliefs, so long as those background beliefs satisfy certain constraints. These latter have developed through application of the same kind of reasoning that they themselves dictate, and change in response to changes in the reasoning-patterns which they themselves generate. This interaction of constraints and reasoning does not eventuate in a vicious circle; rather, what results is a mutual reinforcement, itself rational in a sense that is coherent with well-founded everyday intuitions from which the ideas in question (objectivity and rationality) are descendants, and that makes intelligible the progressive nature of science.

Abstract Cognitive relativists?pragmatists (Stich, Churchland) claim that human cognitive strategies, lacking a common goal, are in addition divergent to the point of incommensurability. They appeal to the study of reasoning heuristics for evidence on cognitive diversity and incorrigibility. It is here argued that no such evidence is offered by the research, which, on the contrary (1) presents heuristics as uniform across great variations; (2) offers advice for correcting and improving human reasoning; and (3) very often postulates a uniformity of core logical strategies, built into reasoning competence. Cognitive research thus supports a moderate rationalism rather than relativism?pragmatism.

This paper is an attempt to reframe the debate of whether medicine is an art or a science in the Aristotelian sense. The recent book of Pellegrino and Thomasma, A Philosophical Basis of Medical Practice, serves as the starting point. Taking clinical interaction as the distinctive feature of medicine, the resemblances of medicine with the characteristics of practical reasoning in the Aristotelian sense are further explored. This comparison proves especially useful in discussing the special status of medical knowledge. Clinical reasoning, resulting in clinical judgments, shows strong similarities with practical reasoning. The application of general principles, instead of deduction from them as in science is essential to both. The ancient concept of practical rationality may therefore be more appropriate while trying to ascribe rationality to medicine than the modern concept of rationality, associated solely with scientific reasoning.

Paper presented at Cognition, Evolution and Rationality: Cognitive Science for the 21st Century. Oporto, September 2002. To appear in a volume based on that conference edited by Antonio Jose Teiga Zilhao.

In this paper, I explore the relationship between epistemic rationality and instrumental rationality, and I attempt to delineate their respective roles in typical instances of theoretical reasoning. My primary concern is with the instrumentalist conception of epistemic rationality: the view that epistemic rationality is simply a species of instrumental rationality, viz. instrumental rationality in the service of one's cognitive or epistemic goals. After sketching the relevance of the instrumentalist conception to debates over naturalism and 'the ethics of belief', I argue that, despite enjoying considerable popularity among both epistemologists and philosophers of science, it is ultimately indefensible. Having thus argued for the distinctness of epistemic and instrumental rationality, I attempt to clarify the role played by each in typical instances of theoretical reasoning. I suggest that being theoretically rational--that is, being proficient with respect to theoretical reasoning--is best construed as a hybrid virtue, inasmuch as it involves manifesting sensitivity to two very different kinds of reasons.

Common sense is on the one hand a certain set of processes of natural cognition - of speaking, reasoning, seeing, and so on. On the other hand common sense is a system of beliefs (of folk physics, folk psychology and so on). Over against both of these is the world of common sense, the world of objects to which the processes of natural cognition and the corresponding belief-contents standardly relate. What are the structures of this world? How does the scientific treatment of this world relate to traditional and contemporary metaphysics and formal ontology? Can we embrace a thesis of common-sense realism to the effect that the world of common sense exists uniquely? Or must we adopt instead a position of cultural relativism which would assign distinct worlds of common sense to each group and epoch? The present paper draws on recent work in computer science (especially in the fields of naive and qualitative physics), in perceptual and developmental psychology, and in cognitive anthropology, in order to consider in a new light these and related questions and to draw conclusions for the methodology and philosophical foundations of the cognitive sciences.