Tuesday, February 1, 2011

Arguments against Functionalism: Block, Jackson and Lewis

Qualia seem to pose a problem for functionalism.  Qualia are just “what it’s like” to have a mental state.  Some examples of qualia are feeling sleepy or a sensation of pain.  Qualia are not necessarily expressed by behaviors.  Our experiences are rich with qualia, though.  While sitting in class, my coffee smells a certain way, my back is a little sore from rock climbing last night and my feet feel comfy in my boots.  These are all qualia that are not manifested in my behaviors and these qualia seem to be irreducible.  In other words, we can only explain these feelings and sensations as feelings and sensations; to explain them in terms of behaviors or neuronal activity misses out on the feeling or the sensation itself.

Jackson thinks that there can be two qualia that give rise to the same functional state.  Functionalism is the view that there is a 1-1 correspondence between mental states and functional states.  If there were two mental states (2 different qualia) that have the same functional state, then this is a counterexample to the functionalist view.   e.g. when a mosquito bites my arm it feels differently from when a horsefly bites my arm.  But these two different mental states have the same functional state: I slap the bug where it is biting me.

4 Features of Qualia: Ineffable, intrinsic, private and directly and infallibly knowable.  Ineffable: unable to be described in words.  They cannot be explained by our words and concepts completely.  Intrinsic: they are inside the subject or the person experiencing.  Private: other people do not have access to my qualia.  Other people cannot observe my qualia like I can.  Directly and Infallibly Knowable: I can never be wrong about how things seem to me.  How something feels is just how it feels to me, which is something that I know just by virtue of experiencing it.

Ned Block’s Absent Qualia Argument Against Functionalism:  Imagine a robot that acts just like humans.  It has all the same behaviors as humans.  However, this machine does not have feelings or qualia.  Block thinks that we cannot say that this robot has mental states or a mind.

Block Argument Formalized:

1. We can imagine a functional system that has all the same functions as me but it is not conscious. It has no qualia.
2. Qualia are mental states.
3. Therefore, some mental states are not functional states.  Functionalism is false.

Jackson’s Red Fred.  Imagine someone who can see more shades of red than the average person (these people exist, they are called tetrachromats).  Jackson says there is no amount of physical information that can explain to us how this person sees the color red.  Knowing all the physical information about Fred is not enough to know what Fred’s experiences of red are!  Mental states are not just functional states that can be described in physical terms!

Jackson’s Color Scientist.  Imagine Mary, a brilliant color scientist.  She only lives in a black and white room.  She is never exposed to colors.  But she reads books about color and spends her whole life learning about color.  She knows everything about color science and color vision.  However, we still can’t say that she knows what it is like to experience colors.  Having all of the scientific physical information about colors is not the same as having a mental experience of colors.   When Mary is finally able to experience color, she learns something new about color: what it is like to experience color! Hence there must be more to color than just the physical information.  Functionalism is false!

Color Scientist Argument Formalized:

1. While in her colorless room, Mary knows all physical facts about color.
2. When she leaves the room, she gets new knowledge about the experience of color.
3. So while in the room, there were facts about color that Mary did not know.
4. Therefore, not all facts about color are physical facts.  Functionalism is false.

Lewis thinks that the third premise of this argument is problematic.  He does admit that the experience of color is different than having physical knowledge of color.  However, he thinks that having an experience of color is NOT getting new knowledge or new facts about color.  Mary may have new know-how, or skill to see color but she does not learn new facts.  Lewis’s response to this objection hinges on the difference between know-how and know-that.  Know-how is something like having a skill.  Know-that is knowing a fact, or a statement is true.  Lewis claims that because premise 3 in the above argument is false, the argument fails.

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