Online research in philosophy

In this paper, I critically assess the enactive account of visual perception recently defended by Alva Noë (2004). I argue inter alia that the enactive account falsely identifies an object’s apparent shape with its 2D perspectival shape; that it mistakenly assimilates visual shape perception and volumetric object recognition; and that it seriously misrepresents the constitutive role of bodily action in visual awareness. I argue further that noticing an object’s perspectival shape involves a hybrid experience combining both perceptual and imaginative elements – an act of what I call ‘make-perceive.’.

The purpose of this paper is to clarify Prajñākaragupta’s view of mental perception ( mānasapratyakṣa ), with special emphasis on the relationship between mental perception and self-awareness. Dignāga, in his PS 1.6ab, says: “mental [perception] ( mānasa ) is [of two kinds:] a cognition of an [external] object and awareness of one’s own mental states such as passion.” According to his commentator Jinendrabuddhi, a cognition of an external object and awareness of an internal object such as passion are here equally called ‘mental perception’ in that neither depends on any of the five external sense organs. Dharmakīrti, on the other hand, considers mental perception to be a cognition which arises after sensory perception, and does not call self-awareness ‘mental perception’. According to Prajñākaragupta, mental perception is the cognition which determines an object as ‘this’ ( idam iti jñānam ). Unlike Dharmakīrti, he holds that the mental perception follows not only after the sensory perception of an external object, but also after the awareness of an internal object. The self-awareness which Dignāga calls ‘mental perception’ is for Prajñākaragupta the cognition which determines as ‘this’ an internal object, or an object which consists in a cognition; it is to be differentiated from the cognition which cognizes cognition itself, that is, self-awareness in its original sense.

Pessoa et al. fail to make a clear distinction between visual perception and subjective visual awareness. Their most controversial claims, however, concern subjective visual awareness rather than visual perception: visual awareness is externalized to the “personal level,” thus denying the view that consciousness is a natural biological phenomenon somehow constructed inside the brain.

Vision has been the primary focus of naturalistic philosophical research concerning perception and perceptual experience. Guided by visual experience and vision science, many philosophers have focused upon theoretical issues dealing with the perception of objects. Recently, however, hearing researchers have discussed auditory objects. I present the case for object perception in vision, and argue that an analog of object perception occurs in auditory perception. I propose a notion of an auditory object that is stronger than just that of an intentional object of audition, but that does not identify auditory objects with the ordinary material objects we see.

I consider the way in which spatial perception is necessary for object seeing. In section 1 I outline the operative conception of object seeing. I consider Cassam’s view that in order to see o, you must see it as spatially located (section 2). I argue that Cassam’s argument is unsound. Cassam’s argument relies on the claim that seeing o requires visual differentiation. But it is not the case that seeing o requires visual differentiation. This is because the following principle is true: if S sees a visible proper part of o, then S sees o, and since there are cases in which S sees a visible proper part of o yet o is not visually differentiated for S , seeing o doesn’t require visual differentiation (section 3). In section 4 I suggest an alternative way of understanding the idea that spatial perception is necessary for object seeing.

How should we think about the role of visual spatial awareness in perception and perceptual knowledge? A common view, which finds a characteristic expression in Kant but has an intellectual heritage reaching back farther than that, is that an account of spatial awareness is fundamental to a theory of experience because spatiality is the defining characteristic of “outer sense”, of our perceptual awareness of how things are in the parts of the world that surround us. A natural counterpart to this idea is to treat self-consciousness as residing in a kind of sense that is fundamentally “inner”, such as introspection or whatever else gives one privileged access to his own mental states as well as the proprioceptive and kinesthetic awareness of bodily position. This division is compatible, of course, with the idea that inner sense provides an awareness of a distinctive kind of “body space”, but it treats that as importantly different from the awareness of the worldly space around one.

In contrast to such a picture, this dissertation proposes an account of visual spatial awareness according to which it is no less a source of self-consciousness than of the awareness of the objects around us, and an account of self-awareness in which visual experience is essentially implicated. I begin by arguing that we should think of visual spatial awareness not as necessary for the individuation of visual sensations but rather as an essential element in the awareness of an experientially objective world. In the subsequent chapters, I argue that in being visually aware of the egocentric positions of the worldly objects around us we are often aware also of our own spatial locations with respect to them, and that the visual experience of the world around one and one’s own situation in it is often an essential component in the knowledge that a human agent will have of his own intentional actions.

Many philosophers have held that it is not possible to experience a spatial object, property, or relation except against the background of an intact awareness of a space that is somehow ‘absolute’. This paper challenges that claim, by analyzing in detail the case of a brain-damaged subject whose visual experiences seem to have violated this condition: spatial objects and properties were present in his visual experience, but space itself was not. I go on to suggest that phenomenological argumentation can give us a kind of evidence about the nature of the mind even if this evidence is not absolutely incorrigible.