The Problem of Consciousness

The Problem of Consciousness


However, our last puzzle about the mind is thought to be a problem for both type physicalist theories and for functionalist theories as well.


There is a very strange quality of our mental lives that makes it very difficult to see how any version of physicalism could be true.


There is a special character, a “what it’s like” to be in certain kinds of mental states:• Seeing red• Being in pain• Getting tickled• Having an orgasm

Nagel calls this the subjective character of experience.


This is one of the most central and important features of our mental life.

But it is also deeply mysterious.

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What It’s Like to Be a Bat

Bats experience the world in a fundamentally different way than we do.

Bats can see, but rely primarily on their hearing to navigate and hunt.


They do this by echolocation: emitting a sound and using the bouncing sound waves to understand things about their environment.


Using this method they can find out things about objects in their environment that we can only usually do by sight:• Distance• Size• Shape• Motion• Even texture


We know alot about bat echolocation:

• We know the principle behind it.• We know nearly everything about bat brains.• We know about their auditory systems and

why they are so sensitive.


We can keep studying bats until we know every physical thing about their brains and their sensory systems.

But, according to Nagel, we still wouldn’t know what it is like to be a bat.


“Even without the benefit of philosophical reflection, anyone who has spent some time in an enclosed space with an excited bat knows what it is to encounter a fundamentally alien form of life…Bat sonar, though clearly a form of perception, is not similar in its operation to any sense that we possess, and there is no reason to suppose that it is subjectively like anything we can experience or imagine.” (229)


No matter how much we study the physical nature of bats, we will never get at what it is like to be one.

The only way to do so is to experience things the way a bat does first-hand.


So it seems as if, no matter how advanced they get, purely physicalist explanations will always leave out something vital about minds.

No physicalist explanation will provide us an understanding the subjective character of experience.


Of course, we know what it is like to be a human and can study the corresponding neuroscience.

But we know what it is like to be us, not because of scientific physicalist explanations, but by experiencing it.– (e.g. explaining red to a blind person)

Mary and The Knowledge Argument

Frank Jackson presents another sort of case designed to establish the same conclusion.


• Mary is captured as a baby and placed in an all black and white room with lighting that makes her skin and such appear similarly without color.

• She becomes the most brilliant scientist in history and learns everything there is to know about color, color-vision, and how the neural system works.


• In short, she knows all the physical facts having to do with seeing red.

• One day Mary is released from her prison and just outside the door she finds an apple (red delicious).

Does Mary learn anything new?


Most people say yes!

She has learned what it is like to see red.


If this is so, we have a powerful argument against physicalism of any kind:

Mary Argument(1) Before leaving her room, Mary knew all the physical facts

having to do with seeing the color red.(2) When Mary sees the apple she learns something new:

namely what it is like to see red.(3) Therefore, what it is like to see red is not a physical fact, or

something that can be learned by studying merely physical facts.


In other words, the conscious experience of seeing red is something that the physical sciences could never explain, even in principle.

The Subjective Character of Experience

As a matter of fact no one has a very good idea of what this “what its like”-ness is, or how it relates to physical things.


Despite all of our knowledge, there still seems to be something inherently “spooky” about minds.


Nagel and others don’t rule out that some physicalist explanation will eventually be offered, but it is almost impossible to imagine what one would look like given what we currently know.


“It would be a mistake to conclude that physicalism must be false…It would be truer to say that physicalism is a position we cannot understand because we do not at present have any conception of how it might be true…At the present time the status of physicalism is similar to that which the hypothesis that matter is energy would have had if uttered by a pre-Socratic philosopher. We do not have the beginnings of a conception of how it might be true.” (237-238)


How to deal with the subjective character of experience is one of the most puzzling questions in philosophy of mind and the cognitive sciences.

Documents

The Problem of Consciousness