This time last year we started a thread of posts on the idea of consciousness. We got somewhat distracted, but here's a follow up... (see the tab on 'Consciousness' to view the previous posts.)
A deterministic argument against dualism
Scientists refute both forms of dualism by resorting to a deterministic argument to explain behaviours like choosing things.
Choosing anything can be explained by pointing to a chain of physical causes and effects which links the initial decision to a combination of brain activity, the nervous system, muscle movement and the environment. The series of physical causes comprising of these factors, it is argued, explain or determine why I chose to wear a blue shirt this morning instead of a white one.
Scientists would have us believe that if they were supplied in advance with a knowledge of all the laws of nature, as well as all of the physical facts relating to my body and environment just a few moments before I chose my blue shirt, they would, in principle, be able to predict the outcome of my decision. The choice of blue shirt, in other words, was fixed in advance by how things were physically.
What are the implications of this?
1. There is no place for a non-physical fact to play a part in the chain of cause and effect – a mental fact or property couldn’t affect the ways things turned out. I would have always chosen the blue shirt.
2. According to dualists, the mind or consciousness is at least partly non-physical and they are committed to the view that the mind or mental properties can affect the way things turn out in the physical world (they want their cake and they want to eat it).
3. But if the deterministic explanation is right, the dualist would be forced to accept that he could omit the mind altogether from his belief system, since it is irrelevant to what goes on in the body when we choose things.
4. However, he might point to the absurdity of the situation; that of course we couldn’t get rid of the mind or consciousness since it makes us what we are.
5. We would then have to point out to him that, according to the ‘chain of cause and effect’ argument, the mind can only affect the outcome of my physical actions if the mind is itself physical.
6. The dualist is left with two alternatives:
a. Holding on to an inconsistant belief in the duality of the mind.
b. Rejecting dualism altogether.
Science appears to win the argument that the world only consists of physical facts. But some people find it difficult to accept that human consciousness is so easily reducible and that our actions are physically pre-determined.
The Black and White room argument against materialism
In the 1980s, the philosopher, Frank Jackson, devised the following thought experiment in a defence of the dualistic position (click on the picture above.)
Imagine a girl, Mary, is born and raised in a room where she can only experience black and white. The scientists who study her have made sure that she has no other colour experiences. She only ever experiences black, white and shades of grey. Mary begins to study science and eventually becomes a world renowned expert in brain science. She discovers everything that goes on inside the brain of people when they have colour experiences – she learns, for example, all the physical facts possible in the chain of causes and effects that explain what happens when people have the experience of seeing red.
Now one day, one of the scientists who’s been studying her development, brings a red tomato into the room. In spite of everything she knows about the ‘experience of red’, Mary is shocked. She does not know that to experience red feels like this. How could she? She’d never experienced redness before. Evidently, Mary has learned a new fact – the fact that experiencing red feels ‘like this’. She thought she knew all the physical facts pertaining to colour experiences. This fact, she now thinks, can’t be a physical fact. She concludes that the ‘experience of red’ and what this experience ‘feels like’ are two different things. The former may be a physical fact, but the latter is not.
According to Jackson, there are two major implications of this thought experiment:
1. there must be something more than physical facts to explain the existence of consciousness.
2. there exists an ‘explanatory gap’ whereby science falls short: it cannot explain everything in terms of an appeal to physical facts alone.
So we are left with our original distinction: is consciousness something irreducibly subjective and private (like the dualists believe) or is it something outward – a physical manifestation of inward states linked to our brain functions and nervous system?
We appear to be nowhere near a definitive answer as to how this piece of flesh we call a human body comes to be full of thoughts and self-awareness...
Scientists refute both forms of dualism by resorting to a deterministic argument to explain behaviours like choosing things.
Choosing anything can be explained by pointing to a chain of physical causes and effects which links the initial decision to a combination of brain activity, the nervous system, muscle movement and the environment. The series of physical causes comprising of these factors, it is argued, explain or determine why I chose to wear a blue shirt this morning instead of a white one.
Scientists would have us believe that if they were supplied in advance with a knowledge of all the laws of nature, as well as all of the physical facts relating to my body and environment just a few moments before I chose my blue shirt, they would, in principle, be able to predict the outcome of my decision. The choice of blue shirt, in other words, was fixed in advance by how things were physically.
What are the implications of this?
1. There is no place for a non-physical fact to play a part in the chain of cause and effect – a mental fact or property couldn’t affect the ways things turned out. I would have always chosen the blue shirt.
2. According to dualists, the mind or consciousness is at least partly non-physical and they are committed to the view that the mind or mental properties can affect the way things turn out in the physical world (they want their cake and they want to eat it).
3. But if the deterministic explanation is right, the dualist would be forced to accept that he could omit the mind altogether from his belief system, since it is irrelevant to what goes on in the body when we choose things.
4. However, he might point to the absurdity of the situation; that of course we couldn’t get rid of the mind or consciousness since it makes us what we are.
5. We would then have to point out to him that, according to the ‘chain of cause and effect’ argument, the mind can only affect the outcome of my physical actions if the mind is itself physical.
6. The dualist is left with two alternatives:
a. Holding on to an inconsistant belief in the duality of the mind.
b. Rejecting dualism altogether.
Science appears to win the argument that the world only consists of physical facts. But some people find it difficult to accept that human consciousness is so easily reducible and that our actions are physically pre-determined.
The Black and White room argument against materialism
In the 1980s, the philosopher, Frank Jackson, devised the following thought experiment in a defence of the dualistic position (click on the picture above.)
Imagine a girl, Mary, is born and raised in a room where she can only experience black and white. The scientists who study her have made sure that she has no other colour experiences. She only ever experiences black, white and shades of grey. Mary begins to study science and eventually becomes a world renowned expert in brain science. She discovers everything that goes on inside the brain of people when they have colour experiences – she learns, for example, all the physical facts possible in the chain of causes and effects that explain what happens when people have the experience of seeing red.
Now one day, one of the scientists who’s been studying her development, brings a red tomato into the room. In spite of everything she knows about the ‘experience of red’, Mary is shocked. She does not know that to experience red feels like this. How could she? She’d never experienced redness before. Evidently, Mary has learned a new fact – the fact that experiencing red feels ‘like this’. She thought she knew all the physical facts pertaining to colour experiences. This fact, she now thinks, can’t be a physical fact. She concludes that the ‘experience of red’ and what this experience ‘feels like’ are two different things. The former may be a physical fact, but the latter is not.
According to Jackson, there are two major implications of this thought experiment:
1. there must be something more than physical facts to explain the existence of consciousness.
2. there exists an ‘explanatory gap’ whereby science falls short: it cannot explain everything in terms of an appeal to physical facts alone.
So we are left with our original distinction: is consciousness something irreducibly subjective and private (like the dualists believe) or is it something outward – a physical manifestation of inward states linked to our brain functions and nervous system?
We appear to be nowhere near a definitive answer as to how this piece of flesh we call a human body comes to be full of thoughts and self-awareness...
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