(Copyright © 1999 Piero Scaruffi | Legal restrictions - Termini d'uso )
With this book
the American philosopher Michael Tye dramatically changed his materialistic
theory of the mind, admitting that phenomenal aspects of mental life are
representational and that they are not to be found in neural events.
First, Tye lists ten problems of phenomenal consciousness, such as ownership (feelings are private to an individual, i.e. "why can't anyebody else feel my feelings?") and perspectival subjectivity (feelings can be understood only by individuals who have felt them), and more traditional issues such as duplicates and inverted qualia.
Tye focuses on "what it is like", on our feelings. Tye attacks physicalism with the view that our feelings are not in the head at all. Neurophysiologists can never explain what it is like to smell or taste. Phenomenal consciousness is not in the neurons. Phenomenal consciousness is in the "representations". Tye separates "phenomenal" consciousness (sensations, perceptions, emotions, feelings) from "higher-order" consciousness. Tye begins with the usual paradox (originally proposed by Jackson) of a scientist who knows everything about a subject, but has not experienced that subject. Tye pictures a scientist who has lived her entire life in a black and white environment but studied all there is to know about colors. She has even seen colored objects on a black and white tv set. She just has not seen them in color. But she knows what color is and what properties it obeys and so forth. Then one day she steps outside her black and white environment and experiences the color of those objects. No matter how much she knew about colors, when she actually sees a red object, she will experience something that she had not experienced before, she will "learn" something that she did not know: the "what it is like" of seeing a color (what Tye calls the "phenomenal character" of seeing a color). There is a difference between objective knowledge of something and subjective experience of something. The latter constitutes the phenomenal consciousness of something. Tye believes that phenomenal states cannot be possibly realized only by neural states. Tye believes that mental states are symbolic representations, but he differs from Fodor in that he does not believe that the representation for a sensation involves a sentence in the language of thought. The belief of something is represented by a symbol structure which is a sentence. The sensation of something is represented by a symbol structure which is not a sentence. The format (the symbolic structure) of a sensory representation is instead maplike: a pattern of activation occurring in a three-dimensional array of cells each containing a symbol and to which descriptive labels are attached. The patterns are analyzed by computational routines that are capable of extracting information and then attaching the appropriate descriptive labels. A sentence would not be enough to represent a sensation, as a sensation includes some kind of "mapping" of the domain it refers to. For example, pain is about the body, and needs a way to represent the body parts that are affected by pain. Sentences lack this maplike representational power. Tye's patterns of activation in those maplike structures are therefore representations of bodily changes that trigger some computational processing. And this is what an emotion is, according to Tye.
Tye's theory of sensations borrows heavily from his theory of mental imagery, where he also presupposes the existence of patterns of activation (in the visual buffer, the three dimensional array of cells), with attached labels, which are interpreted by computational processes. In this case each cell contains (local) information such as (local) orientation, shade of color, texture, and the labels provide information such as the shape or the category of the image. Tye believes that the body is equipped (as a product of evolution) with a set of specialized sensory modules for bodily sensations (for pain, hunger, and so forth) just like the specialized sensory modules for the five senses (and he is thinking of physically different neural regions). Each module is capable of some computation on some symbolic structure.
Additionally, Tye notes that the object of a feeling is non-conceptual: we have different feelings for different shades of red even if we don't have different concepts for those shades of red, we are capable of many more feelings than concepts. Tye concludes that "phenomenal states lie at the interface of the nonconceptual and conceptual domains", at the border between the sensory modules and the cognitive system.
Tye analyzes the phenomenal character ("what it is like") of an experience and its phenomenal content ("what is being experienced"). Tye shows that the phenomenal character of an experience is identical to its phenomenal content (the feeling of pain in a foot cannot be abstracted and remains the fact that it is pain in that foot). Therefore, Tye concludes that phenomenal aspects are a subset of the representational aspects, and not distinct from them.
Tye reiterates that phenomenal character is not neurophysiological, biochemical, or whatever. It is not in the head. But, notwithstanding his technical cogitation of "poised abstract non conceptual intentional contents", it is also not clear in the end where it is.
Because phenomenal character (the "what it is like" feeling) is phenomenal content, experiencing "what it is like" depends on having the approprieta system of concepts: one must have the appropriate system of concepts in order to understand what it is like to experience something. I cannot know what it feels like to be a bat because I don't have the appropriate concepts to feel what a bat feels. Appropriate concepts are predicative and indexical, which can be acquired only from direct experience (past or present).
Tye does not truly solve the "explanatory gap" between phenomenal states and physical states (how subjective feelings arises from neural states which are not subjective): Tye claims that there is no gap, there are two different modes of presentation: the gap is only conceptual. This explains why we cannot know "what it feels like" to be a bat, but does not explain why the bat feels whatever it feels, i.e. how feelings are created from brain states. It is almost as if Tye considered the discussion closed, a' la McGinn, with the idea that we don't have the concepts to understand consciousness, whether the bat's or ours, period.
The book's flaw is a limited knowledge of neurophysiology. FOr example, Tye's thought experiments with "zombie replicas" are pointless: a replica of me that has exactly the same cells that I have would, yes, have my same memory. Zombie replicas with a different memory are neurophysiological oxymorons, period.