Abstract
According to representationalism, phenomenal character supervenes on representational content. According to first-person reports, blindsighters have no phenomenal character in the scotoma, even though their abilities suggest that they have conscious visual representations in the scotoma. The traditional representationalist response is that the representations in the scotoma are either non-conscious or non-visual. Drawing on empirical work, I consider the interpretation that blindsighters are unable to represent—and thus lack the phenomenal character of—luminance in the scotoma. However, they maintain the capacity to represent other visible properties in the scotoma, and thus retain the luminance-lacking phenomenal character of these properties.
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Notes
See Weiskrantz 1986, 1996, 1997, Vision 1998, Kentridge and Heywood 1999, Holt 1999, and Brogaard 2011a, b for empirical overview and philosophical discussion. Although they can identify objects in the scotoma to a degree greater than chance, blindsighters’ capacities are diminished in varying degrees of severity as compared to normal subjects.
Danckert and Rossetti 2005 make a different distinction between types of blindsight in terms of the behaviour shown by subjects: action-blindsight, attention-blindsight, and agnosopsia. This classification does conflict with anything said in this paper.
It must be noted that Block argues that blindsighters have neither access nor phenomenal consciousness in their scotomas, as they require prompting in order to report on the contents of the scotoma which means that the contents of their scotomas are not access conscious. He introduces the notion of a ‘super blindsighter’ who has functionally standard access consciousness but no phenomenal consciousness in the scotoma. Spontaneous actor blindsighters, however, would appear to fit this description.
The modal formulation of representationalism with respect to this paper is that the supervenience relation between phenomenal character and content holds as a matter of empirical fact, or holds by empirical necessity. A stronger claim would be that the supervenience relation holds as a matter of conceptual or metaphysical necessity.
I will take this to be representative of the first-order representationalism in general, although different first-order theories differ in the details.
The explanation of blindsight presented in this paper is compatible with both first and higher-order representationalism, even though it is dialectically more useful to the first-order representationalist for these reasons.
See also Jackson 2003.
As a comparison, think about an auditory version of blindsight, where a subject is aurally aware of, say, an event’s distance but does not have an experience with the auditory phenomenal character of sound.
See Alexander and Cowey 2010 for an updated study of GY. Their results differ, and there are complications it appears with respect to some of Morland et al.’s conclusions but these do not affect the argument in this paper as they do not conclude that GY can perceive luminance in the scotoma.
GY was reporting specifically on visual phenomenal character, but based on Persuad and Lau 2008 we grant him an understanding of experiential phenomenal character per se. However, he surely understands what it is to have specifically visual phenomenal character—after all, he is comparing his normal and affected fields—and that it is a type of general phenomenal character. Thus, his report that he has no phenomenal character in the scotoma should be understood as a report that he has no phenomenal character in the scotoma because he has no visual phenomenal character in the scotoma—where this visual phenomenal character is the type of phenomenal character he has in his normal field and would therefore expect to have in his affected field. Further, we should be careful about any further interpretation of what GY’s answers may mean, for example, with respect to the possibility that he conceives of his affected experiences as amodal because they lack visual phenomenal character. Theoretically, my analysis of the situation does not support this conclusion about affected experiences. They seem to me to still be visual, only they lack the representation and hence phenomenal character of luminance. But as I will argue presently, this does not mean that they are not visual or that they do not have visual phenomenology.
Blind subjects do report some visual phenomena on occasion, but no phenomena that purport to be experiences of external objects, that they report to be instances of sight.
See Dretske 2003 for a clear description of this.
But see note 8.
It does not bear on the argument that the content I have used for exposition here is a singular nonconceptual content.
Thus, it would be incorrect to hold that I am arguing that the subject experiences objects to be luminance-lacking in the sense of this being an experienced negative property. There just is no property perceived, with achromatopsia being an instructive analogy: the achromatopsic subject just experiences no hue, not the negative property of lacking hue. There is an object experienced, x, and it is not experienced as having a property. This obviously happens in every experience; only in these experiences it is not such an important property as hue or, especially, luminance, that is not experienced.
This phenomenon would present a greater level of disorientation, and would be more difficult to process and understand, than similar phenomena where it seems that some visual sensations can be engendered in circumstances without visual stimulus, such as the cross-modal effects demonstrated in Dieter et al. (2014). In our case, the phenomenon is pervasive, as opposed to being effected in laboratory conditions of which the subject is aware. Further, there is, or would be, something genuinely “odd” about such experiences in a stronger fashion than would apply to (most—recall the auditory counterpart of blindsight raised in note 11) other odd experiences, such as bizarre, formless hallucinations, splintered or kaleidoscopic visual experience or something of this kind. I ask the reader again to consider what it would be like to “see in a dark room” or hear without sound.
Let me stress that this is not intended to impugn in any way those blindsighters who have engaged in experimental trials. The philosophy here is extremely complex and nuanced.
In each case, the sub-personal representation of some property is not delivered to visual consciousness. And so the representational analysis of phenomenal character is not refuted by cases of blindsight any more than it is in achromatposia, as blindsight is also understood as a malfunctioning of visual processing which results in a property not being delivered to visual consciousness. What is at stake here is the viability of the representational analysis of phenomenal character in the face of cases of blindsight. A candidate explanation has been give as to why GY, and by tentative extrapolation, all blindsighters report no phenomenal character in their scotoma, even though they appear to pass the behavioural tests for having conscious visual experiences in the scotoma. This explanation is compatible with representationalism as commonly formulated, and with the observations in Morland et al. The argument presented may in the end be incorrect, but it is not obviously incorrect on its face, as for one thing the notions involved in the argument are, as discussed, notions of the utmost philosophical complexity. Nor is it question begging: the representational characterisation of phenomenal character presented is standard in the literature, and the interpretation of Morland et al. is not implausible. The resulting plausibility of this proposal, then, is why I say that simply to assert that either there is no visual experience or phenomenal character without visual representation of luminance is close to question begging; for it does not address, but merely asserts the falsity of, the presented argument.
Of course, it is entirely possible that a blindsighter who can perceive luminance in their scotoma but still displays identical behaviour to other blindsighters will be found. If so, then the argument in this paper will have to be withdrawn. However, until the appearance of such a subject, it hopefully at least stands as an interesting argument for further consideration.
I would like to thank the audience at the University of Geneva for their comments on the content of this paper as well as anonymous referees. This research was partially funded by the Swiss National Science Foundation project "Intentionality as the Mark of the Mental: Metaphysical Perspectives on Contemporary Philosophy of Mind" (CRSI11_127488) and I would like to thank them for their support.
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Peebles, G. Representationalism and Blindsight. Rev.Phil.Psych. 8, 541–556 (2017). https://doi.org/10.1007/s13164-016-0324-1
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DOI: https://doi.org/10.1007/s13164-016-0324-1