Online research in philosophy

In Epistemic Two-Dimensional Semantics, David Chalmers seeks to develop a version of 2-D semantics which can vindicate the rationalist claim that there are constitutive connections between meaning, possibility and a priority. Chalmers lays out different ways of filling in his preferred epistemic approach to 2-D semantics so as to avoid controversial philosophical assumptions. In these comments, however, I argue that there are some distinctively rationalist commitments in Chalmers's epistemic approach to 2-D semantics. I start by explaining why Chalmers's approach requires a canonical language that affords subjects accurate a priori access to the space of possibility. I then argue that traditional worries about rationalism will simply re-emerge as worries about whether there can be a canonical vocabulary and how we could come to recognize one if there were. The moral is that Chalmers's 2-D semantic framework builds in substantive metaphysical and epistemological commitments which stand in need of further defense.

Multicellular organisms are ensembles of quasi-two-dimensional structures (sheets) of various kinds. Why should the development of all organisms be mediated by a quasi-two-dimensional structure? Why does such development avoid a direct confrontation with the third dimension? In this paper, we accept the challenge of addressing this question from the perspective of computational geometry and suggest that the construction of three-dimensional organisms may be explained by the constraints imposed on a bottom-up construction process.

Using dimensional analysis, we demonstrate that it is possible to quantify changes in the topological structure of cardiac dynamics over long periods of time. A method was developed to calculate a dimension-like measure (referred to here as apparent dimension) from a correlation algorithm within a data window of 500 heart beats which is moved in equidistant steps over the time series of the RR intervals over 24 hours. The correspondence between the apparent dimension and the correlation dimension was tested using artificial data sequences. Furthermore 24 hour electrocardiographic recordings of two healthy subjects and of a patient with acute myocardial infarction were examined. The reliability of the analysis could be demonstrated and changes in dimension reflecting physiological as well as pathophysiological changes were observed.

This paper concerns the applications of two-dimensional modal semantics to the explanation of the contents of speech and thought. Different interpretations and applications of the apparatus are contrasted. First, it is argued that David Kaplan's two-dimensional semantics for indexical expressions is different from the use that I made of a formally similar framework to represent the role of contingent information in the determination of what is said. But the two applications are complementary rather than conflicting. Second, my interpretation of the apparatus is contrasted with that of David Chalmers, Frank Jackson, and David Lewis. It is argued that this difference reflects a contrast between internalist and externalist approaches to the problem of intentionality.

This article reports the results of using a specially designed scaled questionnaire to investigate the dualistic properties of epistemic style. The scale is introduced as a measure of individual difference in epistemic style, conceptualized within the framework of dual-process notions of cognitive function. The study examined several psychometric components of the measure, including dimensional structure, distributional characteristics, and indications of construct validity. The instrument, called the Epistemic Preference Indicator, was found to be a reliable and valid measure of two dimensions that are negatively related-each reflecting incompatible epistemic assumptions and approaches to solving knowledge-dependent problems. Theoretical speculations are made concerning the nature of epistemic dualism and the dimension of cognitive processing that may underlie the two proposed epistemic preferences or styles.

Two-dimensional approaches to semantics, broadly understood, recognize two "dimensions" of the meaning or content of linguistic items. On these approaches, expressions and their utterances are associated with two different sorts of semantic values, which play different explanatory roles. Typically, one semantic value is associated with reference and ordinary truth-conditions, while the other is associated with the way that reference and truth-conditions depend on the external world. The second sort of semantic value is often held to play a distinctive role in analyzing matters of cognitive significance and/or context-dependence.

David’s epistemic understanding of two-dimensional semantics has these two features. First, although he considers at least two construals of epistemically possible worlds, on one of them they are centered metaphysically possible worlds. Second, David intends epistemic two-dimensional semantics to yield a theory of propositional-attitude content, as well as having application to the semantics of natural language expressions. These two features come together in David’s “The Components of Content,” where he deploys the apparatus of epistemic two-dimensional semantics to provide an account of propositional-attitude content, and where, for reasons of simplicity and familiarity, epistemically possible worlds are taken to be centered metaphysically possible worlds. My talk is about this account of content.

Scott Soames’ Reference and Description contains arguments against a number of different versions of two-dimensional semantics. After early chapters on descriptivism and on Kripke’s anti-descriptivist arguments, a chapter each is devoted to the roots of twodimensionalism in “slips, errors, or misleading suggestions” by Kripke and Kaplan, and to the two-dimensional approaches developed by Stalnaker (1978) and by Davies and Humberstone (1981). The bulk of the book (about 200 pages) is devoted to “ambitious twodimensionalism”, attributed to Frank Jackson, David Lewis, and me. After a quick overview of two-dimensional approaches, I will focus on Soames’ discussion of ambitious twodimensionalism. I will then turn to a system advocated by Soames that is itself strikingly reminiscent of a two-dimensional approach. Two-dimensional semantic theories are varieties of possible-worlds semantics on which linguistic items can be evaluated relative to possibilities in two different ways, yielding two sorts of intensional semantic values, which can be seen as two “dimensions” of meaning. The second dimension is the familiar sort of Kripkean evaluation in metaphysically possible worlds, so that necessarily coextensive terms (such as ‘Hesperus’ and ‘Phosphorus’ or ‘water’ and ‘H2O’) always have the same semantic value. The first dimension behaves differently, so that there are typically at least some cases where necessarily coextensive terms have different semantic values on the first dimension. For this reason, the two-dimensional framework is sometimes seen as a way of granting many of the insights of a Kripkean approach to meaning (on the second dimension), while retaining elements of a Fregean approach to meaning (on the first dimension).