The Neurophilosophy of Subjectivity

The Neurophilosophy of Subjectivity Pete Mandik Associate Professor and Chair of Philosophy Coordinator, Cognitive Science Laboratory William Paterson University, New Jersey USA

Primary Goal

To show that the thesis that phenomenal character is subjective is

1) an empirical claim

2) for which we have no good reason to believe.

Overview

Subjectivity and the Philosophy of Mind

The Neurophilosophy of Consciousness, Character, and Knowing What it is Like

The Structure of Concepts Defense of Subjectivity

The Content of Concepts Defense of Subjectivity

Time permitting: An appendix!

Section 1

A first stab at subjectivity:

It’s whatever would explain the alleged inability of humans to know what its like to be bats and the blind to know what it is like to see red.

It’s the Nagel-Jackson Property.

A second stab:

(K): For all types of phenomenal character, in order to know what it is like to have a conscious experience with a phenomenal character of a type, one must have, at that or some prior time, a conscious experience with a phenomenal character of the same type.

A second stab:

(K): For all types of phenomenal character, in order to know what it is like to have a conscious experience with a phenomenal character of a type, one must have, at that or some prior time, a conscious experience with a phenomenal character of the same type.

Objection: Hume’s missing shade of blue.

A third stab:

(K+): For at least one type of phenomenal character, in order to know what it is like to have a conscious experience with a phenomenal character of a type, one must have, at that or some prior time, a conscious experience with a phenomenal character of a relevantly similar type.

So-called phenomenal concepts

What might make K+ true?

Phenomenal concepts: concepts constitutively related (perhaps as whole to part) to the phenomenal characters they are concepts of.

“ RED!” / “ RED!”

Things I don’t like:

K+

Phenomenal concepts

Section 2

Neurophilosophy of consciousness

Levels of visual processing in the human nervous system

What is the progression of levels?

Egocentric-to-Allocentric transformations

Highlevel (Frontal Cortex and Hippocampus) Allocentric reps Intermediate-level (IT and PP) Egocentric/Allocentric Hybrid reps Low-level (LGN and V1) Egocentric reps

Pure Allocentric

Pure Egocentric Retinocentric Body-centered Limited viewpoint invariance Amodal Category knowledge The Allocentric-Egocentric Interface The reciprocally influencing representations jointly comprise a conscious state

Neurophilosophy of character

Phenomenal character is the content of the representations at the a-e interface

The Allocentric-Egocentric Interface The reciprocally influencing representations jointly comprise a conscious state

On knowing what it is like

Perception is the automatic conceptual exploitation of information carried by sensations about environmental and bodily events.

Introspection of sensation is the automatic conceptual exploitation of information carried by sensations about themselves.

When the sensations are in appropriately reciprocal interactions with the elicited concepts, the introspection involved is the kind relevant to discussions of knowing what it is like.

HOT!

Our question becomes…

Can those concepts be had without having the experiences with the phenomenal characters they are concepts of?

?????

Section 3

The feed-forward network proposal for phenomenal concepts

A certain kind of empiricism holds for feed-forward networks: no concepts without their experiential targets

Concepts as attractors in activation space

Criticisms of the feed-forward network proposal

Feed-forward networks (FFNs), lacking lateral and recurrent connections, are poor models of consciousness.

For similar reasons FFNs are poor models of concepts, for they cannot account for inference (if inference is to be modeled as something other than simply a response to a stimulus).

If we abandon FFNs…

…then a neurophilosophical reconstruction of the phenomenal concepts proposal involves a commitment to the impossibility of signals along recurrent and lateral connections sufficing for the installation of a concept of phenomenal character.

Section 4

Uniquely represented perceptual contents?

The proposal: uniquely detectable perceptible properties (like Dennnett’s Jell-O Box) entail uniquely representable perceptible properties

Uniquely represented perceptual contents?

PROBLEM: Even if there were environmental properties that entered into detection-supporting causal interactions with only certain sensory states, it seems dubious that those sensory states constitute the only representations of those properties.

Suppose Jones has such sensory states and Smith does not. Even if Jones’ sensory states are the unique detectors of those environmental properties, Smith can still represent those properties. Smith can represent them under a description such as “the environmental properties uniquely detected by Jones' sensory states”.

Uniquely represented introspective contents?

The proposal: Jell-O boxes again, only this time in your head.

“ RED!” /

Uniquely represented introspective contents?

My strategy against this proposal: to raise skeptical doubts, via the story of Hyperbolic Mary, about whether there are any properties uniquely represented in introspection.

Hyperbolic Mary

Hyperbolic Mary knows of the existence of chimerically colored afterimages.

Hyperbolic Mary

Hyperbolic Mary and Larry have seen all normal colors and no chimerical colors.

But only Hyperbolic Mary knows the theory that predicts chimerical colors.

Who’s more surprised?

Appendix

Torin Alter’s Objection: Deviant phenomenal knowledge is irrelevant. A priori derivability of phenomenal from physical facts is.

Appendix

My response:

1. There is a possible non-phenomenal description, D, of RoboMary that entails that she is in state of knowing P. D entails KP. (Alter seems to grant this).