Gary Hatfield

This article first refines the question of Kant's relation to Hume's skepticism, and then considers the evidence for Kant's attitude toward Hume in three contexts: the A Critique, the Prolegomena, and the B Critique. My thesis is that in the A Critique Kant viewed skepticism positively, as a necessary reaction to dogmatism and a spur toward critique. In his initial statement of the critical philosophy Kant treated Hume as an ally in curbing dogmatism, but one who stopped short of what was really needed: a full critique of reason, to establish the boundaries of metaphysical cognition. Kant found fault with Hume's analyses of cognition and experience, and specifically his failure to see the crucial importance of synthetic a priori cognition in metaphysics. In particular, he held that Hume's empiricist account of cognition could neither explain the synthetic a priori cognition actually found in mathematics and natural science, nor provide a principled account of the limits on what can be known--and what can be thought--through the pure concepts of the understanding. According to Kant, Hume therefore failed in his attempt to determine the limits of metaphysics, whereas Kant succeeded because his transcendental philosophy provided a thorough account of cognition, its structure and limits. In the Prolegomena and the B Critique Kant distinguished his position more sharply from Hume's. He also adopted a more negative attitude toward "skeptical idealism" than before; but he attributed such skepticism to Descartes, not Hume. Prior to the B Critique Kant did not see Hume as attacking natural science or ordinary cognition. In none of the three works was Kant's main aim to "answer the skeptic." His primary aim was what he said it was: to firmly establish the boundary of metaphysics, by discovering the elements of human cognition and fixing its proper domain. His purported discoveries about the limits of metaphysical cognition meant that the traditional objects of metaphysical knowledge, God, the soul, and the world as it is in itself, are unknowable, hence that traditional metaphysics itself is impossible. Besides settling the possibility or impossibility of metaphysics, his findings would also prevent the illegitimate extension of principles of sensibility to God and the noumenal self, an extension that would threaten the metaphysics of morals by incorrectly denying the thinkability of noumenal freedom, and that might otherwise lead to "materialism, fatalism, atheism, and freethinking unbelief" (B xxxiv).

Seeking to avoid the typical binary choices between symbolic representations and no representations, or between functionally decomposable psychological processes and no psychological processes, or between direct perception of mind-independent physical properties and indirect perception of sense data, this article proposes that even a clear-thinking friend of Gibson can accept that perception of the environment is mediated by appearances and that such appearances are produced by functionally decomposable, rule-instantiating psychological processes. In so doing, it avoids both hyper-intellectualization of the perceptual process and the positing of sense data as immediate objects of perception. It considers notions of perceptual mediation from classical Gestalt psychology, while referencing recent phenomenological arguments showing that perception does not simply conform to mind-independent physical properties. Perception presents objects and scenes under a phenomenal aspect, in a manner suitable to be action-guiding. Finally, it examines neuroscientific decompositions of Gibsonian information pickup mechanisms, finding that such mechanisms are reasonably described as effecting processes of construction. As a separate point, such mechanisms are usefully described as including subpersonal, non-symbolic representations and processes of information integration.

This chapter considers the development of experimental psychology as a distinct discipline from philosophy, a result that arrived more slowly in Britain than in Germany or the United States. The chapter first considers more closely the question of what it means to chart the ‘emergence’ of psychology as a separate discipline. It finds that the usual criteria applied by historians of psychologh, that a discipline arises through institutional structures such as professorships (a specialist career path), journals, and professional socieites, does not fit the British scene. It then surveys some actors’ taxonomies of psychological trends or schools in Britain, looking back from the first quarter of the twentieth century. Finally, it examines connections between philosophy and psychology in the decades surrounding the turn of the twentieth century, involving the problem of the external world and the use of psychology in epistemology.

This edited volume of newly commissioned papers aims to further understanding of the philosophy of perception and its history. It seeks a broad historical coverage, to include works outside the Western tradition and figures only newly prominent within the Western tradition. Its principal theme is the problem of perceptual error, which it asserts has been understudied, at least in antiquity and the middle ages, as has, allegedly, the history of theories of perception more generally. The individual chapters are typically of high quality and add to the extant literature. The focus, as is usual, is on visual perception, but blindness and touch come forward in three chapters on Molyneux's...

Throughout his career, Wundt recognized Völkerpsychologie (VP) as (at first) ancillary to experimental psychology or (later) as its required complement. New scholarship from around 1979 highlighted this fact while claiming to correct a picture of Wundt as a pure associationist, attributed to Boring’s History of Experimental Psychology, by instead emphasizing apperception in Wundt’s scheme (sec. 2). The criticisms of Boring, summarized by Blumenthal in 1980, overshot the mark. Boring’s Wundt was no pure associationist. Both Boring and the seventy-niner historians emphasized psychic activity in Wundt. Section 3 considers Wundt’s endorsements of mental chemistry, elements, association, and psychological explanation via combinations of elements. Section 4 follows Wundt’s changing conceptions of VP; looks into the relations between VP and experiment, especially as regards “higher” mental processes; examines the (sometimes cooperative) interactions between individual (including experimental) psychology and VP; and considers how method, not type of mental process, distinguishes the two branches of psychology. Finally, section 5 acknowledges Wundt’s unification of VP and individual psychology and concludes that although he objected to the Würzburgers’ experimental methods in treating higher mental processes, he did not generally exclude the latter from experimental investigation, contrary to the seventy-niner narrative, which has been widely adopted.

Abstract. Classical constructivists such as Rock and Hoffman contend that the processes of perception are intelligent and construct perceptual experience by going beyond the stimulus information or by creating a percept that deviates from the physical properties of the object. On these terms, Gibson’s theory of perception is anti-constructivist. After reviewing classical constructivism, this article maintains, first, that the phenomenology of visual space shows a deviation from physical spatial properties, by being contracted in depth, even under full cue conditions, a fact that makes trouble for Gibson’s version of direct realism. Second, independently of the first argument, it contends that perception is pervasively constructed in the sense that stimulus information must be transformed to yield perception. Accordingly, perception is radically constructed in its very bones.

This article considers Helmholtz’s relation to philosophy, including Fichte’s philosophy. Recent interpreters find Fichtean influence on Helmholtz, especially concerning the role of voluntary movement in distinguishing subject from object, or “I” from “not-I.” After examining Helmholtz’s statements about Fichte, the article describes Fichte’s ego-doctrine and asks whether Helmholtz could accept it into his sensory psychology. He could not accept Fichte’s core position, that an intrinsically active I intellectually intuits its own activity and posits the not-I as limiting and determining that activity, because that account requires cognitive abilities that conflict with Helmholtz’s claim that the development of spatial perception relies primarily on associative memory and involves no direct awareness of the ego’s activity as such. Helmholtz would have known various accounts of the distinction between subject and object, or self and world, from sensory physiology, including associative accounts invoking voluntary motor movements and accounts describing checks on the perceiver’s activity. Some of the accounts cite Fichte on the I and not-I, but most do not, and none adopt Fichte’s Idealism. Finally, the article examines Helmholtz’s relation to metaphysics, finding that in all periods he rejected Fichtean Idealism and that the modest metaphysics of his mature period is a version of structural realism.

Descartes analysed the mind into various faculties or powers, including pure intellect, imagination, senses, and will. This article focuses on his account of the sensory power, in relation to its Aristotelian background. Descartes accepted from the Aristotelians that the senses serve to preserve the body by detecting benefits and harms. He rejected the scholastic Aristotelian sensory ontology of resembling species, or ‘forms without matter’. For the visual sense, Descartes offered a mechanistic ontology and a partially mechanized account of sensory processes, including some previously ascribed to judgement. He did this in the context of his theory of brain signs that prompt sensations. The article contends that Descartes’s use of the sign-relation was modelled on standard discussions of non-resembling signs in commentaries on Aristotle’s De interpretatione. It follows three uses of the sign-relation: brain states that cause colour sensations; brain states that cause experiences of spatialized contents, such as shapes; and brain states that realize a ‘natural geometry’. It argues that Descartes’s natural geometry does not involve mental operations but physiological mechanisms that co-vary with the distance to seen objects. While retaining the language of sensory powers, Descartes offered a partial mechanization of those powers.

Review of: Husain Sarkar. A Theory of Method. xvii+ 229 pp., bibl., indexes. Berkeley/Los Angeles/London: University of California Press, 1983. $29.95. The subject of this book is best stated in the author's words: "A theory is about the world; a method is about theories; and, a theory of method is about methods" (p. 1). A theory of method seeks to offer a general framework within which to choose among methods. Through critical examination of the positions of Karl Popper, Imre Lakatos, and Larry Laudan, Sarkar develops his own framework for evaluating methods, which includes two bold proposals: that the history of science cannot be used as an arbitrator among methods, and that methods should be chosen by testing the heuristic advice they give about which lines of scientific research to pursue further.

According to the reading offered here, Descartes' use of the meditative mode of writing was not a mere rhetorical device to win an audience accustomed to the spiritual retreat. His choice of the literary form of the spiritual exercise was consonant with, if not determined by, his theory of the mind and of the basis of human knowledge. Since Descartes' conception of knowledge implied the priority of the intellect over the senses, and indeed the priority of an intellect operating independently of the senses, and since, in Descartes' view, the untutored individual was likely to be nearly wholly immersed in the senses, a procedure was needed for freeing the intellect from sensory domination so that the truth might be seen. Hence, the cognitive exercises of the Meditations, modeled not on the sense- and imagination-based exercises of Ignatius of Loyola, but on the Augustinian procedure of turning away from the senses and imagination to perceive the unpicturable with the fleshless eye of the mind.

During the 1630s Descartes recognized that he could not expect all legitimate claims in natural science to meet the standard of absolute certainty. The realization resulted from a change in his physics, which itself arose not through methodological reflections, but through developments in his substantive metaphysical doctrines. Descartes discovered the metaphysical foundations of his physics in 1629-30; as a consequence, the style of explanation employed in his physical writings changed. His early methodological conceptions, as preserved in the Rules and sketched in Part Two of the Discourse, pertained primarily to his early work in optics. By the early 1630s, Descartes was concerned with new methodological problems pertaining to the postulation of micro-mechanisms. Recognition of the need to employ a method of hypothesis led him to lower the standard of certainty required of particular explanations in his mature physics.

Reprint of: Gary Hatfield, Force (God) in Descartes' physics, Studies in History and Philosophy of Science Part A 10 (2):113-140 (1979) Abstract. It is difficult to evaluate the role of activity - of force or of that which has causal efficacy - in Descartes’ natural philosophy. On the one hand, Descartes claims to include in his natural philosophy only that which can be described geometrically, which amounts to matter (extended substance) in motion (where this motion is described kinematically).’ Yet on the other hand, rigorous adherence to a purely geometrical description of matter in motion would make it difficult to account for the interactions among the particles that constitute Descartes’ universe, since the notions of extension and kinematical motion do not in themselves imply any causal agency. There is, after all, no reason to expect that a particle whose single essence is extension, even if we suppose it to be moving, should impart motion to another particle, while conversely, there is no reason to expect a resting particle to hinder the motion of an impinging one. Descartes' hankering for an austere ontology of matter in motion is in danger of excluding causal agency (force, conceived dynmically) from matter. To the modern reader it may seem obvious that Descartes did not get himself into such a fix, since matter in motion so readily reminds us of kinetic energy or of some more primitive notion of force. Yet by no means is it obvious that Descartes attributed causal efficacy to matter in motion per se. Serious scholars have held opposite positions on this issue. Westfall, Gabbey, and others’ have argued that although on the metaphysical plane Descartes attempted to eliminate force from his mechanical universe, nonetheless ‘force is a real feature’ of his mechanical world. The thrust of this view is that Descartes conceived of force as ‘the capacity of a body in motion to act’, by means of impact, upon other bodies. An opposing interpretation, defended here, is that Descartes did in fact deny causal agency to moving matter per se, restricting agency to immaterial substances such as the human mind, angels, and God. The intention of this interpretation is not to de-emphasize the role of matter in motion in Descartes’ explanation of nature, but rather to stress the fact that Descartes did not conceive of this moving matter dynamically.