You can perceive things, in many respects, as they really are. For example, you can correctly see a coin as circular from most angles. Nonetheless, your perception of the world is perspectival. The coin looks different when slanted than when head-on, and there is some respect in which the slanted coin looks similar to a head-on ellipse. Many hold that perception is perspectival because you perceive certain properties that correspond to the “looks” of things. I argue that this view is (...) misguided. I consider the two standard versions of this view. What I call the PLURALIST APPROACH fails to give a unified account of the perspectival character of perception, while what I call the PERSPECTIVAL PROPERTIES APPROACH violates central commitments of contemporary psychology. I propose instead that perception is perspectival because of the way perceptual states are structured from their parts. (shrink)

Mental capacities for perceiving, remembering, thinking, and planning involve the processing of structured mental representations. A compositional semantics of such representations would explain how the content of any given representation is determined by the contents of its constituents and their mode of combination. While many have argued that semantic theories of mental representations would have broad value for understanding the mind, there have been few attempts to develop such theories in a systematic and empirically constrained way. This paper contributes to (...) that end by developing a semantics for a ‘fragment’ of our mental representational system: the visual system’s representations of the bounding contours of objects. At least three distinct kinds of composition are involved in such representations: ‘concatenation’, ‘feature composition’, and ‘contour composition’. I sketch the constraints on and semantics of each of these. This account has three principal payoffs. First, it models a working framework for compositionally ascribing structure and content to perceptual representations, while highlighting core kinds of evidence that bear on such ascriptions. Second, it shows how a compositional semantics of perception can be compatible with holistic, or Gestalt, phenomena, which are often taken to show that the whole percept is ‘other than the sum of its parts’. Finally, the account illuminates the format of a key type of perceptual representation, bringing out the ways in which contour representations exhibit domain-specific form of the sort that is typical of structured icons such as diagrams and maps, in contrast to typical discursive representations of logic and language. (shrink)

An ongoing philosophical discussion concerns how various types of mental states fall within broad representational genera—for example, whether perceptual states are “iconic” or “sentential,” “analog” or “digital,” and so on. Here, I examine the grounds for making much more specific claims about how mental states are structured from constituent parts. For example, the state I am in when I perceive the shape of a mountain ridge may have as constituent parts my representations of the shapes of each peak and saddle (...) of the ridge. More specific structural claims of this sort are a guide to how mental states fall within broader representational kinds. Moreover, these claims have significant implications of their own about semantic, functional, and epistemic features of our mental lives. But what are the conditions on a mental state's having one type of constituent structure rather than another? Drawing on explanatory strategies in vision science, I argue that, other things being equal, the constituent structure of a mental state determines what I call its distributional properties—namely, how mental states of that type can, cannot, or must co‐occur with other mental states in a given system. Distributional properties depend critically on and are informative about the underlying structures of mental states, they abstract in important ways from aspects of how mental states are processed, and they can yield significant insights into the variegation of psychological capacities. (shrink)

Perception is a central means by which we come to represent and be aware of particulars in the world. I argue that an adequate account of perception must distinguish between what one perceives and what one's perceptual experience is of or about. Through capacities for visual completion, one can be visually aware of particular parts of a scene that one nevertheless does not see. Seeing corresponds to a basic, but not exhaustive, way in which one can be visually aware of (...) an item. I discuss how the relation between seeing and visual awareness should be explicated within a representational account of the mind. Visual awareness of an item involves a primitive kind of reference: one is visually aware of an item when one's visual perceptual state succeeds in referring to that particular item and functions to represent it accurately. Seeing, by contrast, requires more than successful visual reference. Seeing depends additionally on meta-semantic facts about how visual reference happens to be fixed. The notions of seeing and of visual reference are both indispensable to an account of perception, but they are to be characterized at different levels of representational explanation. (shrink)

Perception involves the processing of content or information about the world. In what form is this content represented? I argue that perception is widely compositional. The perceptual system represents many stimulus features (including shape, orientation, and motion) in terms of combinations of other features (such as shape parts, slant and tilt, common and residual motion vectors). But compositionality can take a variety of forms. The ways in which perceptual representations compose are markedly different from the ways in which sentences or (...) thoughts are thought to be composed. I suggest that the thesis that perception is compositional is not itself a concrete hypothesis with specific predictions; rather it affords a productive framework for developing and evaluating specific empirical hypotheses about the form and content of perceptual representations. The question is not just whether perception is compositional, but how. Answering this latter question can provide fundamental insights into perception. (shrink)

It is commonly assumed that images, whether in the world or in the head, do not have a privileged analysis into constituent parts. They are thought to lack the sort of syntactic structure necessary for representing complex contents and entering into sophisticated patterns of inference. I reject this assumption. “Image grammars” are models in computer vision that articulate systematic principles governing the form and content of images. These models are empirically credible and can be construed as literal grammars for images. (...) Images can have rich syntactic structure, though of a markedly different form than sentences in language. (shrink)

When interpreting the meanings of visual features in information visualizations, observers have expectations about how visual features map onto concepts (inferred mappings.) In this study, we examined whether aspects of inferred mappings that have been previously identified for colormap data visualizations generalize to a different type of visualization, Venn diagrams. Venn diagrams offer an interesting test case because empirical evidence about the nature of inferred mappings for colormaps suggests that established conventions for Venn diagrams are counterintuitive. Venn diagrams represent classes (...) using overlapping circles and express logical relationships between those classes by shading out regions to encode the concept of non-existence, or none. We propose that people do not simply expect shading to signify non-existence, but rather they expect regions that appear as holes to signify non-existence (the hole hypothesis.) The appearance of a hole depends on perceptual properties in the diagram in relation to its background. Across three experiments, results supported the hole hypothesis, underscoring the importance of configural processing for interpreting the meanings of visual features in information visualizations. (shrink)

A compositional theory of perceptual representations would explain how the accuracy conditions of a given type of perceptual state depend on the contents of constituent perceptual representations and the way those constituents are structurally related. Such a theory would offer a basic framework for understanding the nature, grounds, and epistemic significance of perception. But an adequate semantics of perceptual representations must accommodate the holistic nature of perception. In particular, perception is replete with context effects, in which the way one perceptually (...) represents one aspect of a scene (including the position, size, orientation, shape, color, motion, or even unity of an object) normally depends on how one represents many other aspects of the scene. The ability of existing accounts of the semantics of perception to analyze context effects is at best unclear. Context effects have even been thought to call into question the very feasibility of a systematic semantics of perception. After outlining a compositional semantics for a rudimentary set of percepts, I draw on empirical models from perceptual psychology to show how such a theory must be modified to analyze context effects. Context effects arise from substantive constraints on how perceptual representations can combine and from the different semantic roles that perceptual representations can have. I suggest that context effects are closely tied to the objectivity of perception. They arise from a perceptual grammar that functions to facilitate the composition of reliably accurate representations in an uncertain but structured world. (shrink)

(1) The idea that diffraction of matter particles can only be understood in terms of a temporary wave transformation or 'double manifestation' is an uneconomical ad hoc hypothesis, shattered already in 1923 by the unitary quantum theory of diffraction of Duane which in 1926 became part of the quantum mechanics, with a statistical interpretation of wave-like appearances. (2) Bohr's re-interpretation of Heisenberg's uncertainty of prediction as an indeterminacy of existence rests on an illegitimate literal translation of a wave result into (...) particle language which is at variance with experience as well as with the statistical interpretation. (3) The fact that one can transform the simple and unitary particle mechanics into a complicated wavelike form is only a weak substitute for genuine dualism -- as if one would see dualism in the transformability from the geo- to the heliocentric reference system. (4) The strongest argument against a symmetry of the particle and the wave theory of matter is the explainability of the former in terms of simple postulates of invariance, leaving the wave formalism as a purely ad hoc construction. (shrink)

In his paper ‘The Gibbs Paradox and the Distinguishability of physical Systems’ Robert Rosen discusses the discontinuity of the diffusion entropy S of two gases, A and B.

The present article is written by a theoretical physicist who, for some time, has endeavored to trace the origin of the concepts and principles of quantum theory to an empirical background broader than that afforded by delicate optical and mechanical experiments on a microphysical scale involving the microconstant h. In particular he tried to reduce the dominant role of probability in modern physics to irrefutable evidence of a quite general nature. As long as quantum probability is deduced from experience with (...) seemingly uncontrollable micro-mechanisms—think of radioactive disintegration as the most typical example—there will always be the objection that one day we still may find a hidden causality behind those small scale gambling devices called atoms, although one example of an exactly predictable atomic event would make present-day quantum theory untenable. In order to dislodge the remaining classicists from their fortress of doubt one may try to show that quantum probability is not an alibi for a temporary impotence of predicting microphysical events, but is a positive conclusion drawn from experience of a most general type, namely, from the principle of continuity, the basic tenet of the philosophy of Leibniz. (shrink)

Many students ask, 'What is the point of learning formal logic?' This book gives them the answer. Using the methods of deductive logic, Nelson Lande introduces each new element in exquisite detail, as he takes students through example after example, proof after proof, explaining the thinking behind each concept. Shaded areas and appendices throughout the book provide explanations and justifications that go beyond the main text, challenging those students who wish to delve deeper, and giving instructors the option of confining (...) their course to the basics, or expanding it, when they wish, to more rigorous levels. Lande encourages students to think for themselves, while at the same time providing them with the level of explanation they need to succeed. It is a rigorous approach presented in a style that is informal, engaging, and accessible. Students will come away with a solid understanding of formal logic and why it is not only important, but also interesting and sometimes even fun. It is a text that brings the human element back into the teaching of logic. --Hans Halvorson, Princeton University. (shrink)

The following observations reflect on the moral-psychological value of the form of reading and writing that Nietzsche referred to as the human, all too human, particularly as he saw it embodied in Goethe, and as taken up by Hans Blumenberg in his collection Goethe zum Beispiel.

Bertrand Russell in “New Hopes for a Changing World” writes the following passage: “The science of economics has been wrapped around by the theorists in a series of many veils, which have caused the plain man to suppose that there must be something indecent about its naked form. I think that the only thing to do in view of this situation is to begin at the beginning with matters of such simplicity that the reader may be indignant at finding them (...) mentioned …”. (shrink)

Trotsky wrote his Terrorism and Communism in 1920, as a response to Karl Kautsky’s book of the same title of the previous year. Trotsky’s aim was to win over, to the side of the Bolshevik view of socialism, the various European socialist political parties. Trotsky’s book is a rare document in the history of political thought. It is a candid and impassioned defense of the Bolshevik view that the period of transition to socialism is incompatible with both individual liberties and (...) democratic institutions as we normally understand them, and requires instead a one-party state with unlimited powers, prepared to use instruments of terror and repression to achieve its goals. In two articles that he wrote in the late 1930s, he elaborated on this view: he sought to provide an explicitly philosophical defense of theBolsheviks’ use of terror and repression.Trotsky’s views merit examination for several reasons: first, because they illuminate the ethical underpinnings of the distinctively Bolshevik view of socialism, and second, because they force one to come to terms with the question of how intelligent, reflective, and decent individuals could have advanced policies that strike us today as ghastly. In this paper I try to piece together Trotsky’s arguments as they bear upon both the Civil War and the immediate postwar period of reconstruction. I also examine criticisms of the policies that Trotsky was defending—criticisms that were advanced by Marxists of such disparate stripes as Kaustky, on the one hand, and Rosa Luxemburg, on the other. (shrink)

The Bohr-Heisenberg doctrine of wave-particle duality has been attacked in the past for its methodical defects, over-complication, internal contradictions, its positivistic phenomenalism, etc. The present investigation shows that duality, the doctrine of equivalence of the particle picture and the wave picture of matter, is untenable since its wave part leads to empirically wrong results in the relativistic domain, and violates the postulate of independence of the arbitrary choice of reference system in the non-relativistic realm. Therefore, when methodical objections were never (...) quite conclusive, the physical failure of the duality idea seals its fate irrefutably, together with all its pseudo-philosophical implications. (shrink)

After a brief survey of arguments for a unitary particle theory of matter, offered by the writer in previous publications, the following new items are discussed. (1) The wave part of the dual aspect of matter, resting on the translation formula λ=h/p, is not covariant in the nonrelativistic domain. And relativistically, it is untenable not only on methodological grounds, but because it leads to obvious contradictions to elementary experience, e.g., in the equilibrium between a material oscillator and radiation. (2) The (...) photon story as usually presented is rectified historically and factually. (3) The previous derivation by the writer of quantum mechanical theory from a nonquantal background is supplemented, in order to be conclusive, by the postulate that the general probability relation is to become the ordinary addition law in the average. (4) Quotations from the writings of prominant dualists, intended by the latter to support their ideology, disclose a fantastic disarray of pseudophilosophical standpoints which can be cleared up only by repudiating the alleged dual nature of matter and of light and by ceasing to constantly mix up the contrast between particles and fields with that between particles and waves, and by returning to a strictly unitary aspect. (shrink)