Gary Hatfield

The paper provisionally accepts the goal of Goldman's primary epistemics, which is to seek reliability values for basic cognitive processes, and questions whether such values may plausibly be expected. The reliability of such processes as perception and memory is dependent on other aspects of cognitive structure, and especially on one's "conceptual scheme," the evaluation of which goes beyond primary epistemics (and its dependence on cognitive science) to social epistemics, or indeed to traditional epistemology and philosophy of science. Two general arguments against the plausibility of determining reliability values for the basic cognitive architecture of humans are proposed, one applying Fodor's distinction between input and central systems, and the other invoking a point by Geertz about culture and evolution. Social epistemics is only briefly evaluated, as it is nascent.

Representation and content in some (actual) theories of perception -- Representation in perception and cognition : task analysis, psychological functions, and rule instantiation -- Perception as unconscious inference -- Representation and constraints : the inverse problem and the structure of visual space -- On perceptual constancy -- Getting objects for free (or not) : the philosophy and psychology of object perception -- Color perception and neural encoding : does metameric matching entail a loss of information? -- Objectivity and subjectivity revisited : color as a psychobiological property -- Sense data and the mind body problem -- The reality of qualia -- The sensory core and the medieval foundations of early modern perceptual theory -- Postscript (2008) on Ibn al-Haytham's (Alhacen's) theory of vision -- Attention in early scientific psychology -- Psychology, philosophy, and cognitive science : reflections on the history and philosophy of experimental psychology -- What can the mind tell us about the brain? : psychology, neurophysiology, and constraint -- Introspective evidence in psychology.

This article calls into question the notion that seventeenth-century authors such as Descartes and Leibniz straightforwardly conceived the mind as something "outside" nature. Descartes indeed did regard matter as distinct from mind, but the question then remains as to whether he equated the natural world, and the world of laws of nature, with the material world. Similarly, Leibniz distinguished a kingdom of final causes (pertaining to souls) and a kingdom of efficient causes (pertaining to bodies and motions), but the question remains as to whether he equated nature with the second kingdom alone, or included both kingdoms within nature. Although Kant sundered Leibniz's envisioned connection between the two kingdoms, even he did not place mind fully outside nature.

During the period 1870-1914 the existing discipline of psychology was transformed. British thinkers including Spencer, Lewes, and Romanes allied psychology with biology and viewed mind as a function of the organism for adapting to the environment. British and German thinkers called attention to social and cultural factors in the development of individual human minds. In Germany and the United States a tradition of psychology as a laboratory science soon developed, which was called a 'new psychology' by contrast with the old, metaphysical psychology. Methodological discussion intensified. New syntheses were framed. Chairs were established and Departments founded. Although the trend toward institutional autonomy was less rapid in Britain and France, significant work was done by the likes of Galton and Binet. Even in Germany and America the purposeful transformation of the old psychology into a new, experimental science was by no means complete in 1914. And while the increase in experimentation changed the body of psychological writing, there was considerable continuity in theoretical content and non-experimental methodology between the old and new psychologies. This chapter follows the emergence of the new psychology out of the old in the national traditions of Britain, Germany, and the United States, with some reference to French, Belgian, Austrian, and Italian thinkers. While the division into national traditions is useful, the psychological literature of the second half of the nineteenth century was generally a European literature, with numerous references across national and linguistic boundaries, and it became a North Atlantic literature as psychology developed in the United States and Canada. The order of treatment, Britain, Germany, and the US, follows the center of gravity of psychological activity. The final section considers some methodological and philosophical issues from these literatures.

The chapter concerns some aspects of Russell’s epistemological turn in the period after 1911. In particular, it focuses on two aspects of his philosophy in this period: his attempt to render material objects as constructions out of sense data, and his attitude toward sense data as “hard data.” It examines closely Russell’s “breakthrough” of early 1914, in which he concluded that, viewed from the standpoint of epistemology and analytic construction, space has six dimensions, not merely three. Russell posits a three-dimensional personal or “perspective” space that is inhabited by sense data. This space then forms the basis for constructing the three dimensional space of physics (and of public things). I am concerned with the specifics of this construction: with the properties of the private spaces, the relations among those spaces, and their relation to physical space and to constructed “things,” such as pennies or tables. There are difficulties of interpretation with respect to these relations, which stem from the difficulty of finding a coherent interpretation of Russell’s claim that objects such as tables and pennies look smaller at a greater distance (or look trapezoidal or elliptical from some points of view). I don’t mean to challenge the phenomenal claim that objects do, in some sense, look small in the distance. Rather, I raise difficulties with Russell’s analysis of this fact, in which he appeals to both phenomenal experience and the findings of sensory psychology. I hold that if he wishes to maintain his phenomenal claim about objects appearing smaller with greater distance, he must alter or redescribe aspects of his construction of ordinary things. However, if his construction of things and physical space is based on a problematic description of the private spaces, then his claim that private or perspective spaces are very well known and provide the hard data for knowledge of the physical world faces a challenge.

Two stories have dominated the historiography of early modern philosophy: one in which a seventeenth century Age of Reason spawned the Enlightenment, and another in which a skeptical crisis cast a shadow over subsequent philosophy, resulting in ever narrower "limits to knowledge." I combine certain elements common to both into a third narrative, one that begins by taking seriously seventeenth-century conceptions of the topics and methods central to the rise of a "new" philosophy. In this revisionist story, differing approaches to the central subject matter of early modern metaphysics--knowledge of substances through their essences and causal powers--arise as a result of disagreements about the powers of the human cognitive faculties. Methodological writings are seen as attempts to direct readers in the proper use of their cognitive faculties. The early modern rejection of the Aristotelian theory of cognition ranks equally in importance with rejection of Aristotelian doctrines about nature. Skepticism is more often than not a tool to be used in teaching the reader the proper use of the cognitive faculties, or indeed in convincing the reader of the existence or inexistence of certain cognitive faculties or powers. Instead of early modern "epistemology" or "theory of knowledge," one speaks, with seventeenth century writers, of theories of the cognitive faculties and their implications for the possibility of human knowledge. The early modern rejection of Aristotelian logic can then be seen as reflecting a negative assessment about the fit between syllogistic reasoning and logic as an art of reasoning or thinking which refines the use of the cognitive faculties. Central to this new historiography is the story of the relation between the intellect and senses as cognitive faculties or powers. The development of philosophy from Descartes to Kant can be portrayed as a series of claims about the power of the intellect to know the essences of things, with resulting consequences for ontology and the foundations of natural philosophy. I illustrate this revised narrative by comparing three conceptions of the intellect in three philosophical settings, provided by several late scholastic Aristotelians, Descartes, and Locke. I have two aims: first, to exhibit the central role played by the conception of intellect or understanding in these authors, and, second, to locate their discussions of the cognitive faculties in relation to recent understandings of psychology, epistemology, logic, mind, and their relations. Early modern writings do not easily fit into the modern categories of epistemology and psychology; more generally, the early modern concern with the workings of mind does not coincide with recent conceptions of naturalism. These findings can help us to see problems with our current categories.

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.

Although the “Transcendental Aesthetic” is the briefest part of the first Critique, it has garnered a lion's share of discussion. This fact reflects the important implications that Kant drew from his arguments there. He used the arguments concerning space and time to display examples of synthetic a priori cognition, to secure his division between intuitions and concepts, and to support transcendental idealism. Earlier, in the years around 1770, Kant's investigations into space and time had facilitated his turn toward “critical” philosophy. Prior to that time, Kant's main interests in space and time pertained to physics and metaphysics. As he entered the critical period, he delved into the cognitive basis of our experience of space (and time), and drew his conclusions about their ideality. Kant's doctrines of space and time provoked extensive response in his own time and throughout the nineteenth century. These responses variously concerned the metaphysics, physics, epistemology, psychology, and geometry of space. Throughout the nineteenth century, philosophers, physiologists, and psychologists sought to extend or to refute Kant's theories of space. By the last decades of the nineteenth century, many had rightly concluded that the existence of non-Euclidean geometry as a candidate description of physical space refuted Kant's full doctrine of space - though some have hoped that his position might be saved by restricting it to “visual space.”.

The problem of the Cartesian circle, as it is called, has sparked ongoing debate, which intersects several important themes of the Meditations. Discussions of the circle must address questions about the force and scope of the famous method of doubt introduced in Meditation I, and they must examine the intricate arguments for the existence of God and the avoidance of error in Meditations III to V. These discussions raise questions about the possibility of overturning skepticism, once a skeptical doubt has been introduced. More generally, the problem of the circle resonates with recent questions about the foundations of knowledge: Must we be able to validate our methods of reasoning or of knowing before using them? If we must, wouldn't we be forever stuck at the beginning, unable to use our methods of reasoning or of knowing in their own validation? The problem of the Cartesian circle raises general questions about the validation of reason and the possibility of knowledge. This chapter examines the Cartesian circle in the context of Descartes' central project in the Meditations, to secure the foundations of metaphysics. In carrying out this project, Descartes felt the need, or adopted the strategy, of examining the possibility of human knowledge more generally. Such an examination can be interpreted in various ways. Depending on the interpretation given, the roles assigned to the method of doubt and the proofs about God may differ, thereby altering how we see the problem of the circle. We therefore need first to consider Descartes' metaphysical project along with the methods and strategies he adopted in carrying it out. Subsequently, I explain and evaluate several main approaches to the problem of the circle. The chapter concludes with some reflections on the relation of Descartes' metaphysics of knowledge to other prominent positions in the history of philosophy.

This article critically examines the views that psychology first came into existence as a discipline ca. 1879, that philosophy and psychology were estranged in the ensuing decades, that psychology finally became scientific through the influence of logical empiricism, and that it should now disappear in favor of cognitive science and neuroscience. It argues that psychology had a natural philosophical phase (from antiquity) that waxed in the seventeenth and eighteenth centuries, that this psychology transformed into experimental psychology ca. 1900, that philosophers and psychologists collaboratively discussed the subject matter and methods of psychology in the first two decades of the twentieth century, that the neobehaviorists were not substantively influenced by the Vienna Circle, that the study of perception and cognition in psychology did not disappear in the behaviorist period and so did not reemerge as a result of artificial intelligence, linguistics, and the computer analogy, that although some psychologists adopted the language-of-thought approach of traditional cognitive science, many did not, and that psychology will not go away because it contributes independently of cognitive science and neuroscience.

In this chapter I examine past and recent theories of unconscious inference. Most theorists have ascribed inferences to perception literally, not analogically, and I focus on the literal approach. I examine three problems faced by such theories if their commitment to unconscious inferences is taken seriously. Two problems concern the cognitive resources that must be available to the visual system (or a more central system) to support the inferences in question. The third problem focuses on how the conclusions of inferences are supposed to explain the phenomenal aspects of visual experience, the looks of things. Finally, in comparing past and recent responses to these problems, I provide an assessment of the current prospects for inferential theories. (This paper is reprinted in Hatfield 2009, Perception and Cognition: Essays in the Philosophy of Psychology, Clarendon Press, 124-152.)

This paper serves to introduce the papers from the symposium by the same title, by describing the sort of work done in philosophy of psychology conceived as a branch of the philosophy of science, distinguishing it from other discussions of psychology in philosophy, and criticizing the claims to set limits on scientific psychology in the largely psychologically uninformed literatures concerning "folk psychology' and "wide" and "narrow" content. Philosophy of psychology as philosophy of science takes seriously and analyzes the explanatory structures, conceptual problems, and evidentiary practices of extant scientific psychology.

The chapter begins with an initial survey of ups and downs of contextualist history of philosophy during the twentieth century in Britain and America, which finds that historically serious history of philosophy has been on the rise. It then considers ways in which the study of past philosophy has been used and is used in philosophy, and makes a case for the philosophical value and necessity of a contextually oriented approach. It examines some uses of past texts and of history that reveal limits to noncontextual history, including Strawson's Kant, Rorty's grand diagnosis of the Western tradition, and Friedman on Kant's philosophy of mathematics. It then considers ways in which the history of philosophy may become philosophically deeper by becoming more historical, and instances in which history of philosophy of various stripes has or may deliver a philosophical payoff. Along the way, it urges historians of philosophy to attend not only to individual philosophers and their problems and projects, but also to the larger shape of the history of philosophy and its narrative themes.

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.).

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.

Rene Descartes and William James had "body first" theories of the passions or emotions, according to which sensory stimulation causes a bodily response that then causes an emotion. Both held that this bodily response also causes an initial behavioral response (such as flight from a bear) without any cognitive intervention such as an "appraisal" of the object or situation. From here they differ. Descartes proposed that the initial processes that produce fear and running are entirely mechanical. Even human beings initially run from the bear as a result of physiological processes alone, without mental contribution. These physiological processes also cause a mental passion, which is a cognitive representation of the situation (as regards novelty, benefit, or harm), and which motivates the will to continue the behavior already in progress. According to James, emotions are caused by instinctive bodily responses that are triggered by noncognitive but nonetheless conscious perceptual states. Emotions are bare feelings of internal physiological stirrings that accompany an instinctual response that has evolved through Darwinian natural selection. Jamesian emotions initially have no motivational or cognitive content, which they subsequently acquire through learning. The methodological legitimacy of comparing these positions across the centuries is defended, and the two theories are compared to recent theories.

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'.

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.

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.

The philosophers René Descartes (1596–1650), Nicolas Malebranche (1638–1715), Benedict Spinoza (1632–77), and Gottfried Wilhelm Leibniz (1646–1716) are grouped together as rationalists because they held that human beings possess a faculty of reason that produces knowledge independently of the senses. In this regard, they contrast with empiricist philosophers, such as John Locke and David Hume, who believed that all knowledge arises from the senses. The rationalists contended that proper use of reason would yield the first principles of metaphysics, the most basic science of all. Metaphysics was also called “first philosophy,” and it took as its subject matter nothing less than the basic properties and principles of everything. For our purposes, it is important to note that the rationalists believed that metaphysics could provide foundations for specialized disciplines, including ethics and physics, and also medicine and other applied subjects. The rationalists and their followers developed theoretical positions of ambitious intellectual scope, ranging from metaphysical conclusions about the existence and nature of God to detailed theories of physical and physiological processes. Although they put great store in the faculty of reason for establishing overarching principles, they looked to observation and experience to provide data and evidence for their detailed theories. They took special interest in the metaphysics and physics of the human organism, and this led them to psychological topics concerning the characteristics and principles of animal behavior, the process of sense perception, the passions, and emotions, and appetites, the cognitive operations of the mind (including attention and understanding), and the relation between mental phenomena and bodily processes in the brain and sense organs. The various rationalists, but especially Descartes, made original contributions to these topics. After considering the character of psychology as a discipline in the seventeenth century, we will examine these contributions in turn.

This paper develops an appearance view of perception (focusing on vision). When we see an object, we see it by having it appear some way to us. We see the object, not the appearance; but we see the object via the appearance. The appearance is subjectively conditioned: aspects of it depend on attributes of the subject. We mentally have the appearance and can reflect on it as an appearance. But in the primary instance, of veridical perception, it is the object that we focus on and experience. I contrast this view with naive realism (sometimes called disjunctivism) (Brewer, Campbell, Noe) and with intentionalist or representationalist views, which I call the physical content view (Dretske, Tye, Crane, Hill, Burge). I agree with these views in rejecting sense-data intermediaries and in affirming direct perception, but I argue that direct perception occurs via appearances, making mine a critical direct realism. The other views attempt to explain the spatial content of perception (shape, size, distance) entirely through the physical properties of objects and their physical relation to the perceiver (viewing position). I argue instead that there are ineliminably subjective aspects of normal spatial perception, which are systematically manifested as a lack of full phenomenal constancy. This systematic underconstancy can’t be accounted for at all by a consistent naive realism; for the physical content view, it requires that most of our ordinary perception is classified as illusory, violating the spirit of that view. Accepting phenomenal underconstancy as pervasive, I suggest that our ability to perceive the mind-independent properties of objects depends on developed conceptual abilities. In the final section, I compare my appearance view with the adverbialism of Chisholm and the critical direct realism of Roy Wood Sellars.

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. Reprinted in Descartes, ed. by J. Cottingham, Oxford Readings in Philosophy (Oxford: Oxford University Press, 1998), 281–310.

Review of _Descartes’s Method of Doubt_, by Janet Broughton. Princeton and Oxford: Princeton University Press, 2002. Pp. xv + 217. H/b £22.95, P/b £10.95. The review characterizes Broughton's book on Cartesian doubt as a work that attends to the philosophical significance of Descartes's work while taking seriously his own aims and the historical context of his arguments. The review considers her extensive examination of the method of doubt and her notion of "dependence arguments" as a way of overcoming the doubt. The latter includes her own distinctive take on what she calls the "I exist" argument.

Descartes entitled the Sixth Meditation "The existence of material things, and the real distinction between mind and body." But these topics take up only two paragraphs, about one-third of the way into the Sixth Meditation (which is the longest of the six). The other topics in the Meditation partly pertain to the cognitive faculties that a seeker after knowledge must employ: senses, imagination, and intellect. They also concern the mind–body relation: not only is it to be shown that mind and body are distinct, but also that they are “closely joined” together. The joining of mind to body contributes to explanations of the cognitive faculties, for such a joining is, in Descartes’ view, necessary for the operation of sense and imagination, whereas the exercise of the intellect in the pursuit of metaphysical results -- as in his argument for mind–body distinctness -- takes place without the mind interacting with the body. But this still doesn't account for the most sustained discussion in the Sixth Meditation, which concerns the role of the senses in informing us about the world around us. While the trustworthiness of the senses has been under suspicion up to this point in the Meditations, now the senses are rehabilitated. They can serve to acquaint us with the world of bodies, for the purposes of empirical investigation serving natural philosophy but, more usually, for the practical purpose of informing us of potential benefits and harms in our immediate environment. In this regard, Descartes considers the ways in the senses might be subject to local errors or might, if used inappropriately, draw us into systematic error. But the previous results of the Meditations now offer the means for avoiding such systematic error, and the reflections of the Sixth Meditation can guide us toward practical uses of the senses in ways that reduce error. In the end, the senses are found to be trustworthy for the guidance of action, and this trustworthiness extends even to a qualitative experience such as color, which helps us to discriminate among the bodies that we see.

Analytic philosophy arose in the early decades of the twentieth century, with Bertrand Russell and G. E. Moore leading the way. Although some accounts emphasize the role of logic and language in the origin of analytic philosophy, of equal importance is the theme of perception, sense data, and knowledge, which dominated systematic philosophical discussion in the first two decades of the twentieth century in both Britain and America. This chapter examines work on perception and sense data as well as the external world in the analytic tradition in the first half of the twentieth century. After sketching the situation before and just after 1900, it turns to Moore, Russell, and their interlocutors in the teens and twenties, addresses the American scene, looks to subsequent developments in the 1930s and beyond, and finally considers the fates of sense data and the ‘given’ and of the topic of perception more generally.

In philosophical writings from Descartes’ time, the topic of attention attracted notice but not systematic treatment. In Descartes’s own writings, attention was not given the kind of extended analysis that he devoted to the theory of the senses, or the passions, or to the intellect and will. Nonetheless, phenomena of attention arose in relation to these other topics and were discussed in terms of mental operations and, where appropriate, relations to bodily organs. Although not producing a systematic account, Descartes frequently noted attentional phenomena and creatively imagined intricate relations between sensory attention and brain processes. Descartes's observations of attentional phenomena show remarkable breadth, including cases of active mental control of attention and cases in which attention is drawn involuntarily to a novel event (first section). Descartes did not merely observe attentional phenomena; he also offered a framework for understanding them (second section). Part of this framework related attention to the activity of the will. Part also came from his conception of mind-body interaction. He assigned a significant functional role to brain processes in explaining mental phenomena, including aspects of attention. He sometimes moves beyond the usual notions of unidirectional activity or passivity in the process of interaction. Rather, mind and brain are mutually constraining. Mental and physiological processes form a functional unity, in which brain processes contribute to the mental functioning of attention (final section). Furthermore, Descartes was willing to speak of “attention” in the mindless machine portrayed in his Traité de l’homme. That work describes brain states that interact with mind to explain aspects of mental attention. But we must also suppose that these same brain states constitute attention as it occurs in non-human animals, which lack a mind. According to Descartes, although attention is, in the first instance, a mental phenomenon, it can also be ascribed to non-human animals that share brain mechanisms with human beings and the behavior of which can be described as attentively directed toward selected objects in the environment. Translated into French by Olivier Dubouclez.