Daubert’s Naïve Realist Challenge to Husserl

Despite extensive discussion of naïve realism in the wider philosophical literature, those influenced by the phenomenological movement who work in the philosophy of perception have hardly weighed in on the matter. It is thus interesting to discover that Edmund Husserl’s close philosophical interlocutor and friend, the early twentieth-century phenomenologist Johannes Daubert, held the naive realist view. This article presents Daubert’s views on the fundamental nature of perceptual experience and shows how they differ radically from those of Husserl’s. The author argues, in conclusion, that Daubert’s views are superior to those of Husserl’s specifically in the way that they deal with the phenomenon of perceptual constancy

Motion transparency : depth ordering and smooth pursuit eye movements

When two overlapping, transparent surfaces move in different directions, there is ambiguity with respect to the depth ordering of the surfaces. Little is known about the surface features that are used to resolve this ambiguity. Here, we investigated the influence of different surface features on the perceived depth order and the direction of smooth pursuit eye movements. Surfaces containing more dots, moving opposite to an adapted direction, moving at a slower speed, or moving in the same direction as the eyes were more likely to be seen in the back. Smooth pursuit eye movements showed an initial preference for surfaces containing more dots, moving in a non-adapted direction, moving at a faster speed, and being composed of larger dots. After 300 to 500 ms, smooth pursuit eye movements adjusted to perception and followed the surface whose direction had to be indicated. The differences between perceived depth order and initial pursuit preferences and the slow adjustment of pursuit indicate that perceived depth order is not determined solely by the eye movements. The common effect of dot number and motion adaptation suggests that global motion strength can induce a bias to perceive the stronger motion in the back

Nonconceptual content and the nature of perceptual experience

Recent philosophy of mind and epistemology has seen an important and influential trend towards accounting for at least some features of experiences in content-involving terms. It is a contested point whether ascribing content to experiences can account for all the intrinsic properties of experiences, but on many theories of experiences there are close links between the ascription of content and the ways in which experiences are ascribed and typed. The issues here have both epistemological and psychological dimensions. On the one hand, a theory of experiential content has a fundamental role in explaining how knowledge of the world can be acquired through experience. On the other hand, there are important psychological questions about the phenomenology of experiences and the conditions under which content ascriptions are made. The debate about whether experiences have conceptual or nonconceptual content is highly relevant to both the epistemological and psychological issues. This is apparent in the work of Gareth Evans who is often cited as the first philosopher to propose a theory of nonconceptual content. This paper will explicate and examine Evans' theory. In particular, attention will be paid to Evans' claim that perceptually-derived information with nonconceptual content can only qualify as a perceptual experience when it serves as input to a thinking, concept-applying, and reasoning system. We will sketch out a theoretical approach to the nature of nonconceptual content that builds on Evans' insight but does not follow him in this restrictive claim

The effect of transparency on recognition of overlapping objects

Are overlapping objects easier to recognize when the objects are transparent or opaque? It is important to know whether the transparency of X-ray images of luggage contributes to the difficulty in searching those images for targets. Transparency provides extra information about objects that would normally be occluded but creates potentially ambiguous depth relations at the region of overlap. Two experiments investigated the threshold durations at which adult participants could accurately name pairs of overlapping objects that were opaque or transparent. In Experiment 1, the transparent displays included monocular cues to relative depth. Recognition of the back object was possible at shorter durations for transparent displays than for opaque displays. In Experiment 2, the transparent displays had no monocular depth cues. There was no difference in the duration at which the back object was recognized across transparent and opaque displays. The results of the two experiments suggest that transparent displays, even though less familiar than opaque displays, do not make object recognition more difficult, and possibly show a benefit. These findings call into question the importance of edge junctions in object recognitio

On the Possibility of Hallucinations

Many take the possibility of hallucinations to imply that a relationalist account, according to which perceptual experiences are constituted by direct relations to ordinary mind-independent objects, is false. The common reaction among relationalists is to adopt a disjunctivist view that denies that hallucinations have the same nature as perceptual experiences. This paper proposes a non-disjunctivist response to the argument from hallucination by arguing that the alleged empirical and a priori evidence in support of the possibility of hallucinations is inconclusive. A corollary upshot of the article is that whether hallucinations are possible or not is still an open empirical question

Introspection without Judgment

The focus of this paper is introspection of phenomenal states, i.e. the distinctively first-personal method through which one can form beliefs about the phenomenology of one’s current conscious mental states. I argue that two different kinds of phenomenal state introspection should be distinguished: one which involves recognizing and classifying the introspected phenomenal state as an instance of a certain experience type, and another which does not involve such classification. Whereas the former is potentially judgment-like, the latter is not. I call them, respectively, reflective introspection and primitive introspection. The purpose of this paper is to argue that primitive introspection is a psychologically real phenomenon. I first introduce the distinction and provide some preliminary motivation to accept it (§1). After some set-up considerations (§2), I present my central argument for the existence of a non-classificatory kind of introspective state (§3), what I call the ‘argument from phenomenal-concept acquisition’. Finally, I briefly present some reasons why my distinction may be important for various philosophical debates (§4)

The Super Justification Argument for Phenomenal Transparency

ABSTRACT In Consciousness and Fundamental Reality, Philip Goff argues that the case against physicalist views of consciousness turns on ‘Phenomenal Transparency’, roughly the thesis that phenomenal concepts reveal the essential nature of phenomenal properties. This paper considers the argument that Goff offers for Phenomenal Transparency. The key premise is that our introspective judgments about current conscious experience are ‘Super Justified’, in that these judgments enjoy an epistemic status comparable to that of simple mathematical judgments, and a better epistemic status than run of the mill perceptual judgments. After presenting the key ideas in the ‘Super Justification Argument’, I distinguish two Super Justification theses, which vary according to the kind of introspective judgments that they take to be Super Justified. I argue that Goff’s case requires ‘Strong Super Justification’, according to which a wide range of introspective judgments about conscious experience are Super Justified. Unfortunately, it turns out that Strong Super Justification is implausible and not well-supported by examples. In contrast, a weaker Super Justification thesis does not require anything like Phenomenal Transparency and, indeed, can be explained by physicalistic accounts of phenomenal concepts

Laminar Cortical Dynamics of 3D Surface Perception: Stratification, transparency, and Neon Color Spreading

How does the laminar organization of cortical circuitry in areas VI and V2 give rise to 3D percepts of stratification, transparency, and neon color spreading in response to 2D pictures and 3D scenes? Psychophysical experiments have shown that such 3D percepts are sensitive to whether contiguous image regions have the same relative contrast polarity (dark-light or lightdark), yet long-range perceptual grouping is known to pool over opposite contrast polarities. The ocularity of contiguous regions is also critical for neon color spreading: Having different ocularity despite the contrast relationship that favors neon spreading blocks the spread. In addition, half visible points in a stereogram can induce near-depth transparency if the contrast relationship favors transparency in the half visible areas. It thus seems critical to have the whole contrast relationship in a monocular configuration, since splitting it between two stereogram images cancels the effect. What adaptive functions of perceptual grouping enable it to both preserve sensitivity to monocular contrast and also to pool over opposite contrasts? Aspects of cortical development, grouping, attention, perceptual learning, stereopsis and 3D planar surface perception have previously been analyzed using a 3D LAMINART model of cortical areas VI, V2, and V4. The present work consistently extends this model to show how like-polarity competition between VI simple cells in layer 4 may be combined with other LAMINART grouping mechanisms, such as cooperative pooling of opposite polarities at layer 2/3 complex cells. The model also explains how the Metelli Rules can lead to transparent percepts, how bistable transparency percepts can arise in which either surface can be perceived as transparent, and how such a transparency reversal can be facilitated by an attention shift. The like-polarity inhibition prediction is consistent with lateral masking experiments in which two f1anking Gabor patches with the same contrast polarity as the target increase the target detection threshold when they approach the target. It is also consistent with LAMINART simulations of cortical development. Other model explanations and testable predictions will also be presented.Air Force Office of Naval Research (F49620-01-1-0397); Office of Naval Research (N00014-01-1-0624