In this thesis, I both analyze the phenomenology of vision from a geometrical point of view, and also develop certain connections between that geometrical analysis and the mind body problem. In order to motivate the need for such an analysis, I first show, by means of a refutation of direct realism, that visual space is never identical with any of the physical objects being indirectly "seen" by constituting color arrangements in it. It thus follows that the geometry of visual space (...) may be quite different from the Euclidean geometry of physical space, and I proceed to analyze that geometry. ;I argue that topologically, visual space is two dimensional, inasmuch as regions of it are capable of being bounded by a line, such as the borders around the various objects constituted in it. An apparent paradox arises here though, inasmuch as we posess phenomenal depth perception, which is particularly striking during binocular vision, and thus the question arises as to how the binocular depth cue of retinal disparity is registered phenomenally in a two dimensional space. I resolve this apparent paradox by arguing that the internal metric struture of this space can be apprehended phenomenally, and can serve as such a phenomenal depth cue. It is shown that holistically, this metric structure is elliptical, since for example marginal distortions in wide-angle photography are not present in visual space, and it is also noted that there is a tendency towards size constancy in visual perception. It is shown from these geometrical considerations that visual space posseses a variable curvature, with that curvature being determined by the physical depths of objects constituted in the space. ;Finally, I investigate what bearing the preceding geometrical conclusions have on the question of how events in visual space may be causally determined by neural events in the brain. The classical isomorphic theory of Gestalt psychology is then reinterpreted in light of my analysis of the geometry of visual space. (shrink)

I argue that perception is necessarily situation-dependent. The way an object is must not just be distinguished from the way it appears and the way it is represented, but also from the way it is presented given the situational features. First, I argue that the way an object is presented is best understood in terms of external, mind-independent, but situation-dependent properties of objects. Situation-dependent properties are exclusively sensitive to and ontologically dependent on the intrinsic properties of objects, such as their (...) shape, size, and color, and the situational features, such as the lighting conditions and the perceiver’s location in relation to the perceived object. Second, I argue that perceiving intrinsic properties is epistemically dependent on representing situation-dependent properties. Recognizing situation-dependent properties yields four advantages. It makes it possible to embrace the motivations that lead to phenomenalism and indirect realism by recognizing that objects are presented a certain way, while holding on to the intuition that subjects directly perceive objects. Second, it acknowledges that perceptions are not just individuated by the objects they are of, but by the ways those objects are presented given the situational features. Third, it allows for a way to accommodate the fact that there is a wide range of viewing conditions or situational features that can count as normal. Finally, it makes it possible to distinguish perception and thought about the same object with regard to what is represented. (shrink)

Introduction In 1709 George Berkeley published his first substantial work, An Essay towards a New Theory of Vision. As a contribution to the theory of ...

Chapter I: The Geometry of Visibles 1 . The N on- Euclidean Geometry of Visibles In the chapter "The Geometry of Visibles" in Inquiry into the Human Mind, ...

This book is the one to put into the hands of those who have been over-impressed by Austin 's critics....[Warnock's] brilliant editing puts everybody who is concerned with philosophical problems in his debt.

Thomas Reid (1710–1796) presented a two-dimensional geometry of the visual field in his Inquiry into the human mind (1764), whose axioms are different from those of Euclidean plane geometry. Reid’s ‘geometry of visibles’ is the same as the geometry of the surface of the sphere, described without reference to points and lines outside the surface itself. Interpreters of Reid seem to be divided in evaluating the significance of his geometry of visibles in the history of the discovery of non-Euclidean geometries. (...) The question will be reexamined with particular attention given to his unpublished manuscripts. These include comments on Saccheri’s work and Reid’s repeated attempts to derive Euclid’s parallel postulate from the axioms of incidence. (shrink)

Thomas Reid, the Scottish natural and moral philosopher, was one of the founding members of the Aberdeen Philosophical Society and a significant figure in the Scottish Enlightenment. Reid believed that common sense should form the foundation of all philosophical inquiry. He criticised the sceptical philosophy propagated by his fellow Scot David Hume and the Anglo-Irish bishop George Berkeley, who asserted that the external world did not exist outside the human mind. Reid was also critical of the theory of ideas propagated (...) by Locke and Descartes, arguing that it was incompatible with physical and experiential facts. For Reid, our senses demonstrate that the external world must exist, and this work is organised in chapters examining each of the senses in turn. The book, based on his lectures, was first published in 1764 when Reid was a regent professor at King's College, Aberdeen, and was reissued in 1818. (shrink)

Perceptual experiences inform us about objective properties of things in our environment. But they also have perspectival character in the sense that they differ phenomenally when objects are viewed from different points of view. Contemporary representationalists hold, at a minimum, that phenomenal character supervenes on representational content. Thus, in order to account for perspectival character, they need to indentify a type of representational content that changes in appropriate ways with the perceiver’s point of view. Many representationlists, including Shoemaker and Lycan, (...) argue that such contents are best construed in terms of mind-dependent properties. Other representationalists, including Tye and Dretske, hold that these contents involve only mind-independent properties. Susanna Schellenberg has recently developed an account of perceptual experience that would serve these latter representationalists extremely well. She suggests that we can do justice to the perspectival character of perceptual experience by appeal to representations of a certain type of relational properties, so-called ‘situation-dependent properties.’ In this paper, I critically engage with Schellenberg’s proposal in order to show how mind-independent representationalists can explain perspectival character. I argue that appeal to situation-dependent properties is problematic. I then show that mind-independent representationalists can account for perspectical character by means of scenario contents in Christopher Peacocke’s sense. (shrink)

The issue is obscured by the fact that the word `space' can be used in four different ways. It can be used, first, as a term of pure mathematics, as when mathematicians talk of an `n-dimensional phase-space', an `n-dimensional vector-space', a `three-dimensional projective space' or a `twodimensional Riemannian space'. In this sense the word `space' means the totality of the abstract entities-the `points'-implicitly defined by the axioms. There is no doubt that there exist, iii this sense, non-Euclidean spaces, because all (...) that is claimed by such an assertion is that sets of non-Euclidean axioms constitute possible implicit definitions of abstract entities, that is to say that some sets of non-Euclidean axioms are consistent. If Kant or any other philosopher had denied this, he would have been wrong; but Kant himself took care not to deny it, 2 and there is little reason to suppose that any philosopher concerned about space has been using the word in this, the pure mathematician's, sense. (shrink)

This paper, which has both a historical and a polemical aspect, investigates the view, dominant throughout the eighteenth and nineteenth centuries, that the sense of sight is, originally, not phenomenally three-dimensional in character, and that we must come to interpret its properly two-dimensional data by reference to the sense of 'touch'. The principal argument for this claim, due to Berkeley, is examined and found wanting. The supposedly confirming findings concerning 'Molyneux subjects' are also investigated and are shown to be either (...) irrelevant or disconfirming. Recent investigations on infant and neonatal perception are discussed and are also found to be disconfirming. An innatist version of the theory is then considered and is shown to be undermined by the largely 'Gibsonian' character of early space-perception. Finally three recent arguments in favour of the theory - two from psychologists, one from a philosopher - are considered and answered. (shrink)

Presents a concise and comprehensive analysis of George Berkeley’s thought and the impact of his intellectual contributions to philosophy In this latest addition to the Blackwell Great Minds series, noted scholar of early modern philosophy Margaret Atherton examines Berkeley’s most influential work and demonstrates the significant conceptual impact of his ideas in metaphysics and the philosophy of religion. A concise and rigorous primer on Berkeley’s essential writings and contributions to modern philosophy Written by a leading scholar of early modern philosophy (...) Offers insight into the foundations of modern metaphysical and religious philosophy Equips readers to find firm footing in Berkeley’s wider body of published work in the canon of Western philosophy. (shrink)

This influential study of Kant in which Strawson seeks to detach the true analytical and critical achievement of Kant's work from the unacceptable metaphysics with which it is entangled. This title available in eBook format. Click here for more information.Visit our eBookstore at: www.ebookstore.tandf.co.uk.

In a brief but remarkable section of the Inquiry into the Human Mind, Thomas Reid argued that the visual field is governed by principles other than the familiar theorems of Euclid—theorems we would nowadays classify as Riemannian. On the strength of this section, he has been credited by Norman Daniels, R. B. Angell, and others with discovering non-Euclidean geometry over half a century before the mathematicians—sixty years before Lobachevsky and ninety years before Riemann. I believe that Reid does indeed have (...) a fair claim to have discovered a non-Euclidean geometry. However, the real basis of Reid’s geometry of visibles is subtle and easy to misidentify. My main aim in what follows is to make clear what the real basis is, separating it from several fallacious or irrelevant considerations on which Reid may seem to be relying. A secondary aim is to air the worry that Reid’s case for his geometry can succeed only at the cost of compromising the achievement for which Reid is best known—his direct realist theory of perception. (shrink)

In his 'Inquiry', Reid claims, against Berkeley, that there is a science of the perspectival shapes of objects ('visible figures'): they are geometrically equivalent to shapes projected onto the surfaces of spheres. This claim should be understood as asserting that for every theorem regarding visible figures there is a corresponding theorem regarding spherical projections; the proof of the theorem regarding spherical projections can be used to construct a proof of the theorem regarding visible figures, and vice versa. I reconstruct Reid's (...) argument for this claim, and expose its mathematical underpinnings: it is successful, and depends on no empirical assumptions to which he was not entitled about the workings of the human eye. I also argue that, although Reid may or may not have been aware of it, the geometry of spherical projections is not the only geometry of visible figure. (shrink)

The subject of this investigation is the role of conventions in the formulation of Thomas Reid’s theory of the geometry of vision, which he calls the ‘geometry of visibles’. In particular, we will examine the work of N. Daniels and R. Angell who have alleged that, respectively, Reid’s ‘geometry of visibles’ and the geometry of the visual field are non-Euclidean. As will be demonstrated, however, the construction of any geometry of vision is subject to a choice of conventions regarding the (...) construction and assignment of its various properties, especially metric properties, and this fact undermines the claim for a unique non-Euclidean status for the geometry of vision. Finally, a suggestion is offered for trying to reconcile Reid’s direct realist theory of perception with his geometry of visibles.While Thomas Reid is well-known as the leading exponent of the Scottish ‘common-sense’ school of philosophy, his role in the history of geometry has only recently been drawing the attention of the scholarly community. In particular, several influential works, by N. Daniels and R. B. Angell, have claimed Reid as the discoverer of non-Euclidean geometry; an achievement, moreover, that pre-dates the geometries of Lobachevsky, Bolyai, and Gauss by over a half century. Reid’s alleged discovery appears within the context of his analysis of the geometry of the visual field, which he dubs the ‘geometry of visibles’. In summarizing the importance of Reid’s philosophy in this area, Daniels is led to conclude that ‘there can remain little doubt that Reid intends the geometry of visibles to be an alternative to Euclidean geometry’;1 while Angell, similarly inspired by Reid, draws a much stronger inference: ‘The geometry which precisely and naturally fits the actual configurations of the visual field is a non-Euclidean, two-dimensional, elliptical geometry. In substance, this thesis was advanced by Thomas Reid in 1764...’, 2 The significance of these findings has not gone unnoticed in mathematical and scientific circles, moreover, for Reid’s name is beginning to appear more frequently in historical surveys of the development of geometry and the theories of space., 3Implicit in the recent work on Reid’s ‘geometry of visibles’, or GOV, one can discern two closely related but distinct arguments: first, that Reid did in fact formulate a non-Euclidean geometry, and second, that the GOV is non-Euclidean. This essay will investigate mainly the latter claim, although a lengthy discussion will be accorded to the first. Overall, in contrast to the optimistic reports of a non-Euclidean GOV, it will be argued that there is a great deal of conceptual freedom in the construction of any geometry pertaining to the visual field. Rather than single out a non-Euclidean structure as the only geometry consistent with visual phenomena, an examination of Reid, Daniels, and Angell will reveal the crucial role of geometric ‘conventions’, especially of the metric sort, in the formulation of the GOV. Consequently, while a non-Euclidean geometry is consistent with Reid’s GOV, it is only one of many different geometrical structures that a GOV can possess. Angell’s theory that the GOV can only be construed as non-Euclidean, is thus incorrect. After an exploration of Reid’s theory and the alleged non-Euclidean nature of the GOV, in 1 and 2 respectively, the focus will turn to the tacit role of conventionalism in Daniels’ reconstruction of Reid’s GOV argument, and in the contemporary treatment of a non-Euclidean visual geometry offered by Angell. Finally, in the conclusion, a suggestion will be offered for a possible reconstruction of Reid’s GOV that does not violate his avowed ‘direct realist’ theory of perception, since this epistemological thesis largely prompted his formulation of the GOV. (shrink)

This is Thomas Reid's greatest work. It covers far more philosophical ground than the earlier, more popular Inquiry. The Intellectual Powers and its companion volume, Essays on the Active Powers of Man, constitute the fullest, most original presentation of the philosophy of Common Sense. In the process, Reid provides acutely critical discussions of an impressive array of thinkers but especially of David Hume. In Reid's eyes, Hume had driven a deep tendency in modern philosophy to its ultimate conclusions by creating (...) a phantom-world of so-called 'ideas' that sprang from objects of observation; the self was a conglomeration of perceived ideas; and the will as the source of action was nothing but the balance of passionate impulses.Reid's Common Sense philosophy answers these problems by suggesting that sceptics, such as Hume, unavoidably affirm what they purport to deny, namely the existence of a stable external world, of other minds, of the continuity of their own minds, and of their own and other people's ability to ascribe and accept responsibility for actions. We can understand all of this by proper empirical observation and philosophical analysis of the activity of the mind. Reid's major positive contribution to philosophy is a detailed account of the various innate powers of the mind. While particularly influential in the first half of the nineteenth century, Reid's work has retained a significant role in philosophy, not least in recent years. At the same time, his role in the Scottish Enlightenment is becoming much better understood.This is the only properly established text. It is accompanied by manuscript lectures on the nature and immortality of the soul, as well as helpful editorial annotation and introduction, making it useful to a wide variety of readers.Key FeaturesAccurate, reliable and critically established textThe Introduction explains the work's genesis and its place in Reid's systemAnnotations provide an understanding of Reid's contextAn Appendix contains manuscript material covering an important topic not represented in the hitherto published work. (shrink)