The approach to critical realism, by D. Drake.--Pragmatism versus the pragmatist, by A. O. Lovejoy.--Critical realism and the possibility of knowledge, by J. B. Pratt.--The problem of error, by A. K. Rogers.--Three proofs of realism, by G. Santayana.--Knowledge and its categories, by R. W. Sellars.--On the nature of the datum, by C. A. Strong.

Much as we would like to conceive empirical thought as rationally grounded in experience, pitfalls await anyone who tries to articulate this position, and ...

What is the relationship between our perceptions and reality? What is the relationship between the mind and the body? These are questions with which philosophers have grappled for centuries, and they are topics of considerable contemporary debate as well. Hilary Putnam has approached the divisions between perception and reality and between mind and body with great creativity throughout his career. Now, in _The Threefold Cord: Mind, Body, and World,_ he expounds upon these issues, elucidating both the strengths and weaknesses of (...) current schools of thought. With his characteristic wit and acuity, Putnam offers refreshing solutions to some of philosophy's most vexing problems. Putnam first examines the problem of realism: is objective truth possible? He acknowledges the deep impasse between empirical and idealist approaches to this question, critiquing them both, however, by highlighting the false assumption they share, that we cannot perceive the world directly. Drawing on the work of J. L. Austin and William James, Putnam develops a subtle and creative alternative, which he calls "natural realism." The second part of the book explores the mind-body question: is the mind independent of our interactions with the physical world? Again, Putnam critically assesses two sharply antithetical contemporary approaches and finds them both lacking. _The Threefold Cord_ shows the entire mind-body debate to be miscast and draws on the later work of Wittgenstein, once more advancing original views on perception and thought and their relationship with both the body and the external world. Finally, Putnam takes up two related problems--the role of causality in human behavior and whether or not thoughts and sensations have an "existence" all their own. With Putnam's lucid prose and insightful examples, _The Threefold Cord_ loosens the Gordian knots into which philosophy has bound itself over the issue of epistemology. (shrink)

A common objection to sense-datum theories of perception is that they cannot give an adequate account of the fact that introspection indicates that our sensory experiences are directed on, or are about, the mind-independent entities in the world around us, that our sense experience is transparent to the world. In this paper I point out that the main force of this claim is to point out an explanatory challenge to sense-datum theories.

This article seeks the origin, in the theories of Ibn al-Haytham (Alhazen), Descartes, and Berkeley, of two-stage theories of spatial perception, which hold that visual perception involves both an immediate representation of the proximal stimulus in a two-dimensional ‘‘sensory core’’ and also a subsequent perception of the three dimensional world. The works of Ibn al-Haytham, Descartes, and Berkeley already frame the major theoretical options that guided visual theory into the twentieth century. The field of visual perception was the first area (...) of what we now call psychology to apply mathematics, through geometrical models as used by Euclid, Ptolemy, Ibn al-Haytham, and Descartes (among others). The article shows that Kepler’s discovery of the retinal image, which revolutionized visual anatomy and entailed fundamental changes in visual physiology, did not alter the basic structure of theories of spatial vision. These changes in visual physiology are advanced especially in Descartes' Dioptrics and his L'Homme. Berkeley develops a radically empirist theory vision, according to which visual perception of depth is learned through associative processes that rely on the sense of touch. But Descartes and Berkeley share the assertion that there is a two-dimensional sensory core that is in principle available to consciousness. They also share the observation that we don't usually perceived this core, but find depth and distance to be phenomenally immediate, a point they struggle to accommodate theoretically. If our interpretation is correct, it was not a change in the theory of the psychology of vision that engendered the idea of a sensory core, but rather the introduction of the theory into a new metaphysical context. (shrink)

Gary Hatfield examines theories of spatial perception from the seventeenth to the nineteenth century and provides a detailed analysis of the works of Kant and Helmholtz, who adopted opposing stances on whether central questions about spatial perception were fully amenable to natural-scientific treatment. At stake were the proper understanding of the relationships among sensation, perception, and experience, and the proper methodological framework for investigating the mental activities of judgment, understanding, and reason issues which remain at the core of philosophical psychology (...) and cognitive science. (shrink)

Descartes developed an elaborate theory of animal physiology that he used to explain functionally organized, situationally adapted behavior in both human and nonhuman animals. Although he restricted true mentality to the human soul, I argue that he developed a purely mechanistic (or material) ‘psychology’ of sensory, motor, and low-level cognitive functions. In effect, he sought to mechanize the offices of the Aristotelian sensitive soul. He described the basic mechanisms in the Treatise on man, which he summarized in the Discourse. However, (...) the Passions of the soul contains his most ambitious claims for purely material brain processes. These claims arise in abstract discussions of the functions of the passions and in illustrations of those functions. Accordingly, after providing an intellectual context for Descartes’s theory of the passions, especially by comparison with that of Tho- mas Aquinas, I examine its ‘machine psychology’, including the role of habituation and association. I contend that Descartes put forth what may reasonably be called a ‘psychology’ of the unensouled animal body and, correspondingly, of the human body when the soul does not intervene. He thus conceptually distinguished a mechanistically explicable sensory and motor psychology, common to nonhuman and human animals, from true mentality involving higher cognition and volition and requiring (in his view) an immaterial mind. (shrink)

This paper argues for the reality of qualia as aspects of phenomenal experience. The argument focuses on color vision and develops a dispositionalist, subjectivist account of what it is for an object to be colored. I consider objections to dispositionalism on epistemological, metaphysical, and 'ordinary' grounds. I distinguish my representative realism from sense-data theories and from recent 'representational' or 'intentional' theories, and I argue that there is no good reason to adopt a physicalist stance that denies the reality of qualia (...) as phenomenally available intentional contents in Brentano's original sense of 'intentionality'. (shrink)

Descartes' Meditations is one of the most widely read philosophical texts and has marked the beginning of what we now consider as modern philosophy. It is the first text that most students of philosophy are introduced to and this Guidebook will be an indispensable introduction to what is undeniably one of the most important texts in the history of philosophy. Gary Hatfield offers a clear and concise introduction to Descartes' background, a careful reading of the Meditations and a methodological investigation (...) of its main themes. As with all the Guidebooks, this is an exemplary companion to any reading of the Meditations. (Note: This edition has been superseded by Gary Hatfield (2014), The Routledge Guidebook to Descartes' Meditations.). (shrink)

In this provocative book, Fred Dretske argues that to achieve an understanding of the mind it is not enough to understand the biological machinery by means of...

The chapter examines some common assumptions regarding the shape of the history of theories of mind. It questions the conception that the Scientific Revolution resulted in placing the mind “outside of nature.” During the seventeenth century, the followers of Descartes routinely placed study of the mind, or, at least, mind–body interaction, within “physics” considered as a science of nature in general (and so including physics in the narrow sense, biology, and psychology). By the end of the eighteenth century, many authors (...) treated the psychological and the physical as distinct areas of investigation (with points of contact, to be sure), both amenable to natural scientific study. Another assumption is that, prior to behaviorism, the notion of “the psychological” was equivalent to “the mental.” And yet, during the seventeenth century psychological phenomena were assigned to both sides of the mind–body divide: the Cartesians and their allies offered (nonmentalistic) mechanistic explanations for the sensory and behavioral capacities that human beings share with animals, while also holding that some aspects of mental life (including consciousness, free will, conceptual language, and general intelligence) require an immaterial mind. Finally, from the late eighteenth century onward, some have maintained that if mental states are reached only by introspection then they cannot be studied objectively. The chapter argues that the standard version of this objection misunderstands the nature of introspection, and it mounts a reply founded on Wundt’s methodological discussions and making reference to the perceptual investigations of the Gestalt psychologists. (shrink)

During the seventeenth century the major cognitive faculties--sense, imagination, memory, and understanding or intellect--became the central focus of argument in metaphysics and epistemology to an extent not seen before. The theory of the intellect, long an important auxiliary to metaphysics, became the focus of metaphysical dispute, especially over the scope and powers of the intellect and the existence of a `pure' intellect. Rationalist metaphysicians such as Descartes, Spinoza, and Malebranche claimed that intellectual knowledge, gained independently of the senses, provides the (...) framework for constructing a new theory of nature. Other writers, including Hobbes and the early Gassendi, denied the existence of a distinct intellectual faculty, and so challenged the metaphysicians' abilities directly to perceive the essences of substances. The theory of the senses, which had long been a part of philosophical discussion, took on a new urgency, for adherents of the new corpuscularian philosophy needed to replace the dominant Aristotelian theory of real sensory qualities and sensible species. The revival of skepticism and a renewed interest in method also brought the faculties into prominence, for skeptical challenges typically were directed toward the faculties of sense and understanding, and the theory of method was conceived as providing instructions for the proper use of one's cognitive equipment. The theory of the faculties, then, is an important key to theories of knowledge in the seventeenth century. Indeed, rather than speaking of seventeenth century epistemology, it would be less anachronistic and more informative to speak of theories of cognition. The familiar (and over-stated) point that epistemology became fundamental to metaphysics during that century can then be restated as the point that the theory of faculties became central in metaphysical dispute. (shrink)

This chapter considers philosophical problems concerning non-human (and sometimes human) animals, including their metaphysical, physical, and moral status, their origin, what makes them alive, their functional organization, and the basis of their sensitive and cognitive capacities. I proceed by assuming what most of Descartes’s followers and interpreters have held: that Descartes proposed that animals lack sentience, feeling, and genuinely cognitive representations of things. (Some scholars interpret Descartes differently, denying that he excluded sentience, feeling, and representation from animals, and I consider (...) the evidence for these interpretations as well.) Given that Descartes denied any sort of soul to animals, his other philosophical commitments entailed that he must explain the vital and sensitive powers of non-human animals through purely material causes. Indeed, he welcomed this task, for he was engaged in the larger project of providing purely mechanistic explanations for all natural phenomena of the material world. Animal bodies form functional unities that are adapted to environmental circumstances. In his new physics, Descartes sought to discover or hypothesize material mechanisms that would explain the physiological and behavioral capacities of animals, including how they maintain themselves by seeking food and drink, reproduce themselves, and modify their behavior to fit current circumstances. Metaphysically, his new perspective raised the problem of accounting for the functional unity of the animal body considered as a purely material construction, devoid of an active, organizing power such as the sensitive soul. Descartes’s project becomes even more challenging if we ask whence come such mechanisms that are capable of performing the functions of living things. Officially, Descartes endorsed the accepted theological orthodoxy, that God designed and created the bodily mechanisms of humans and animals. However, in his natural philosophy he set himself the task of explaining the origin of animals as part of the natural development of the universe out of an original chaotic soup of material particles. Within this naturalistic perspective, he must explain how, through purely material processes, the functionally organized bodies of living things (plants and animals) could be produced from non-living matter. Without a designing creator, how do animal bodies arise that are capable of digesting food, growing, reproducing, and performing the behaviors needed to preserve life and health? (shrink)

In Philosophy and the Mirror of Nature (1979), Richard Rorty locates the perceived ills of modern philosophy in the "epistemological turn" of Descartes and Locke. This chapter argues that Rorty's accounts of Descartes' and Locke's philosophical work are seriously flawed. Rorty misunderstood the participation of early modern philosophers in the rise of modern science, and he misdescribed their examination of cognition as psychological rather than epistemological. His diagnostic efforts were thereby undermined, and he missed Descartes' original conception of a general (...) physics, and Locke's probabilist analysis of the grounds for rational belief. (shrink)

This chapter compares rationalist theories of sense perception to previously held theories of perception (especially of vision) and examines rationalist accounts of sensory qualities and sensory representation, of the role of the sense-based passions in guiding behavior, of the epistemological benefits and dangers of sense perception, and of mind–body relations. Each section begins with Descartes, the first major rationalist of the seventeenth century. The other major rationalists, Malebranche, Spinoza, and Leibniz, and also lesser known figures such as Pierre Regis, Jacques (...) Rohault, and Antoine Le Grand, were well acquainted with Descartes' work. Indeed, the first three were each deeply influenced by Descartes in their early years before developing their own philosophical systems, and the latter three were all advocates of Descartes' philosophy (perhaps with slight revision). Each of the major rationalists, while sharing some positions in common, developed a distinctive metaphysics of perception and of the mind–body relation. Earlier sections chart these differences and a final section sums up common features and touches on the continuing significance of their views. (shrink)

This chapter reconsiders the notion of perceptual constancy from the ground up. It distinguishes the phenomenology of perceptual constancy and stability from a functional characterization of perception as aiming at full constancy. Drawing on this distinction, we can attend to the phenomenology of constancy itself, and ask to what extent human perceivers attain constancy, as usually defined. Within this phenomenology, I distinguish phenomenal presentations of spatial features and color properties from categorizations, conceptualizations, and judgments that underlie verbal or other responses (...) to those presentations. Although phenomenal presentation and categorization commonly co-occur, they are distinct aspects of experience. After reviewing several standard descriptions of constancy, I present laboratory findings and my own phenomenological descriptions by way of confirming that, although perception "tends toward" constancy, human perceivers do not usually attain full constancy for either spatial or chromatic properties (as many investigators acknowledge). For spatial perception, I find that the phenomenology has been systematically misdescribed, and I offer a more adequate description of the phenomenology of everyday spatial perception. However, my greatest quarrel with previous theory concerns the functional aim of the constancies. I argue not only that perception does not achieve full constancy but that we should not characterize it as aiming for full constancy. Rather, perception seeks a stability of representation suitable for guiding our actions and which can also, as needed, enable us to classify and re-identify objects by phenomenally presented properties such as shape, size, or color. Further, I argue that theorists should not confuse these classifications with the qualitative character of phenomenal experience. My arguments underscore the need to distinguish phenomenal representation (better, "presentation") from conceptual categorization, and to distinguish perceptual presentations from subsequent processes that are involved in responding to them. (shrink)