A popular argument against dualism (in the folk world, not among professional philosophers) is that the mind can be affected by taking drugs, or by brain damage, and so on. So clearly, the mind must be created by or be caused by the brain, and hence dualism is false. Here is the argument formally:
1. All mental events can be affected by physical events
2. No immaterial things can be affected by physical events
3. Therefore, no mental event is immaterial (i.e., dualism is false)
But no dualist would accept premise 2. Of course dualists think that the (immaterial) mind can be affected by matter! Stub your toe, experience the (immaterial) mental event of pain.
This ever-popular argument, perhaps the main argument against dualism in the world of the layman, is unsound.
Showing posts with label dualism. Show all posts
Showing posts with label dualism. Show all posts
Wednesday, June 19, 2013
Friday, September 14, 2012
Dualism: List of Theories
Arguments for Dualism
Most of the arguments for dualism involve showing that there is a fundamental difference in the properties of matter as opposed to those of mind. If X = Y, then anything true of X should be true of Y and vice versa. If X has properties that Y does not have, then X is not Y. For example, the mind can logically exist without matter (such as brain-in-a-vat scenarios), but matter cannot logically exist without matter.
Substance Dualism
Most famously associated with Rene Descartes, substance dualism says that the mind is a completely different kind of "stuff" than matter. You are a non-physical person just "riding" or "driving" your physical body. The biggest problem with substance dualism is explaining how a non-physical substance can get into a cause/effect relationship with matter.
There are roughly three types of substance dualism, based on how they handle this interaction problem:
Property Dualism
Concedes that the arguments for a non-physical mind are successful, but maintains that the mind is still caused by the physical brain. So there is still only one type of stuff (matter), but if arranged the right way can give rise to properties that are not present in physics.
There are roughly two types of property dualism:
Most of the arguments for dualism involve showing that there is a fundamental difference in the properties of matter as opposed to those of mind. If X = Y, then anything true of X should be true of Y and vice versa. If X has properties that Y does not have, then X is not Y. For example, the mind can logically exist without matter (such as brain-in-a-vat scenarios), but matter cannot logically exist without matter.
Substance Dualism
Most famously associated with Rene Descartes, substance dualism says that the mind is a completely different kind of "stuff" than matter. You are a non-physical person just "riding" or "driving" your physical body. The biggest problem with substance dualism is explaining how a non-physical substance can get into a cause/effect relationship with matter.
There are roughly three types of substance dualism, based on how they handle this interaction problem:
- Interactive Substance Dualism (or Cartesian Dualism): Descartes' version. He didn't really have a good explanation, but thought that there was no obvious problem with interaction.
- Occasionalism: The mind and body do not interact. Rather, when you decide to do something physical (like move your arm), God causes your physical arm to move at the same time.
- Parallelism: The mind and body also do not interact. Rather, all events are synched up from the beginning of time, like two clocks synched with each other. When you lift your arm, that event was destined to happen at the same time as your willing of your arm to move.
Property Dualism
Concedes that the arguments for a non-physical mind are successful, but maintains that the mind is still caused by the physical brain. So there is still only one type of stuff (matter), but if arranged the right way can give rise to properties that are not present in physics.
There are roughly two types of property dualism:
- Emergentism: Claims that the physical brain gives rise to the (non-physical) mind, and that the mind can affect the body (and vice versa). I.e., two way interaction.
- Epiphenomenalism : Claims that the physical brain gives rise to the (non-physical) mind, but that the mind cannot affect the body. I.e., one way
interaction.
Thursday, March 22, 2012
Introduction to Intentionality #2: Materialist Solutions
In the first post, we looked at the problem of intentionality and how it may be a serious challenge to materialistic and naturalistic theories of mind. There hasn't been a successful explanation of intentionality in physical terms thus far, but there are several attempts. This article will look at a few of these.
I. Conceptual Role
Let's consider the possibility that something represents something else in virtue of the fact that it relates to other representations. So for example your thought about Mt Everest refers to Mt Everest because of its relationship to other neighboring thoughts, such as "mountains are large landforms" and "the Himalayas are a mountain range in China and Nepal", and so forth. So a thought represents something by being in context with other thoughts that also represent things. This web of representations, each
The obvious question is that, while this nicely explains how a thought has a specific meaning, it doesn't explain how anything has any meaning at all. All these other thoughts also have meaning, and if they get their meaning from the context of other thoughts, then you go to infinity and never end up explaining how any thought has any meaning at all in the first place.
The answer is that these thoughts rest on a Background of non-intentional capacities for acting with the world. At the foundational level, there is, for example, the behavioral capacity for climbing a mountain, and this forms the foundation of the thoughts and beliefs having the meaning that they do.
The problem with this is that there is a fundamental difference between motion, and intentional acting. A rock rolling down a hill is not intentional action; it's just matter in motion. An unconscious behavior, such as fleeing from a predator, is an intentional action since it is directed towards a specific end. So the behavior at the bottom level would still be intentional, if it is to explain anything, and so it leaves intentionality still unreduced.
II. Causal
An improvement of this theory is to recognize that for a thought to represent something else, it must connect somehow with the external world. So if there is a constant conjunction between an external stimulus, such as the vision of Mt Everest, along with the internal brain event that processes it, then eventually the thought or brain event will come to represent its referent.The external stimulus is causing the thought to point to something.
This theory is appealing but has several problems.
The first problem is that it can't account for misrepresentation. You might have a thought about Mt Everest, but in fact be mistaken and your thought is really about the neighboring mountain Lohtse, because it is at night and conditions are bad and you are mistaken. So in this case your thought about Mt Everest is caused, not by Mt Everest, but by Lohtse.
This further raises yet a further problem. If Mt Everest or Lohtse-at-night can cause your thought about Mt Everest, then why should the thought be considered a thought about [Mt Everest], rather than a thought about [Mt Everest or Lohtse-at-night]? Why does Everest get to win and be what the thought is about? A possible response to this is to say that the stimulus, Mt Everest, normally causes the thought, but other stimuli are parasitic on it, such as Lohtse-at-night. The second thought, caused by Lohtse-at-night, would not exist without the "parent" thought, caused by Mt Everest.
But there are even more problems.
Your thought about Mt Everest might be caused, not by Mt Everest, but by hallucinogenic drugs, or by the Matrix. Perhaps we live in the Matrix and there is no actual Mt Everest, in which case your thought about it was not caused by it at all, because it doesn't even exist. Your thought about Mt Everest was caused instead by computer software input directly into your brain from the Matrix.
Also, this theory explains why a certain thought has a certain meaning rather than some other meaning, but it doesn't explain how thoughts can have any meaning at all in the first place.
And finally, there is yet another problem with the causal account. There is a long causal chain, from the stimulus that is the object of thought all the way to the brain processes. The light photons travel from the sun, hit the snow of Mt Everest, travel through the air, into the eyes, where they cause electrons to travel up the optic nerve to the visual cortex, where they cause other brain processes, and so on. This is one long chain of causal processes, with Mt Everest at one end and the thought that represents Mt Everest on the other. Yet, if we remove what we already know to be the two end points of this causal chain, and just look at it in purely materialistic terms, we just have one long causal chain with no specific end points that are objective. If the photons from the sun are A, the travel through the air is B, Mt Everest is E, travelling through the air from the mountain to our eyes is F through M, entering our eyes is N, hitting our retinas is O, travelling through our optic nerve is P, and so on, then there are no objective endpoints. And so we would have to bring in another mind to say that T represents E, rather than M representing F. And bringing in another mind to assign meaning is once again to leave mind, and representation, unreduced and unexplained.
III. Biological Semantics
So if both these theories leave much to be desired, let's turn instead to biological theories of intentionality. We could think of representations and intentionality as biological functions, designed by natural selection. The need to run away from predators is a biological function, and perhaps over time this function becomes a representation. Of predators, say.
This theory avoids the misrepresentation problem. In this case, your thought that represents bears is caused, not by bears themselves, but by the desire to avoid bears. So therefore if you mistakenly believe that an old stump is a bear, this can be explained as a result of your representation being caused by the desire to avoid predators.
One problem with this theory is that it can't account for sophisticated and abstract beliefs and thoughts. Concerning math, philosophy, or other high level reasoning. Natural selection wouldn't be able to program such functions in.
Biological theories of intentionality also can't deal with the disjunction problem. If your desire to avoid both bears and stumps-that-look-like-bears has been wired in by evolution, then your thought that represents bears would actually represent bears or stumps-that-look-like-bears, not bears specifically.
Some philosophers, in response to this, suggest that this is not a problem with this theory. That in fact thoughts do not have exact meaning, and there is no specific fact of the matter about what any particular thought is. But this seems wrong. When you think about Mt Everest, there is a specific thing you are thinking about: Mt Everest. There is a specific object of your thought. Your thought about Mt Everest isn't a thought about "maybe Mt Everest, maybe Lohtse, maybe chocolate milk, whatever". It's about a specific object, or referent. However, even if we accept that our thoughts are not about specific referents, and accept the biological theory of intentionality, there remains yet another problem with it.
If the theory can explain why certain thoughts have certain meanings, but to explain why any thought has any meaning at all in the first place, it has to appeal to biological functions. Behavior directed at specific ends, or goals, or aims. But the whole point of Darwinian evolution is that it explains life without having to refer to functions, purposes, teleology, and such. The function of the stomach is not to digest food. The stomach causes the digestion of food, but it has no function. But if intentionality, or the meaning of thoughts, is to be explained in terms of biological function, then this theory illegitimately brings in teleology, which is anathema to materialistic theories.
IV. Instrumentalism
So let's look at a final materialist theory of intentionality.
We could take several different positions towards various things. If we need to know how to move an elephant, we need to know it's weight, size, and so on. So we could take the physical stance towards it. If we need to know what the elephant's heart does, we can take the design stance. We can AS IF the heart were designed for a particular function: pumping blood. Even though it wasn't designed. And finally, if we need to understand elephant behavior, we can act AS IF the elephant were consciously aware of its behavior. If the elephant trumpets to warn its herd of a predator, we can act AS IF the elephant were consciously deciding to do so rather than just acting on blind instinct. This is called the "intentional stance." We ACT LIKE the elephant is figuring things out mentally, and has intentionality, but really it doesn't. Or think of a DVR. We can take the intentional stance towards it, speaking about it as if it "knows" our favorite shows and is "smart enough" to record them, even though we know it isn't really.
So this theory says that our own intentionality reduces to just that: we act AS IF we have intentionality, but really we do not.
A few obvious problems pop up right away. For us to be taking a conscious "stance" towards anything presupposes intentionality. If our minds were not really directed towards specific targets or goals, then we couldn't take any stance towards anything.
A possible reply is that a subprocess in the mind assigns intentionality to thoughts. This is called a "homunculus". A little mind inside your mind. And then we would need to explain the intentionality of the homunculus by postulating another homunclus inside his head, and so on. Normally, this would lead to an infinite regress and thus a non-explanation, but philosopher Daniel Dennet proposes stupider and stupider homunculi, until we get down to the bottom level of no homunculi at all. But to bridge that gap, from no homuncli to the first, and stupidest, homunclus, is not just a wide gap but an uncrossable one. For, to leap from non-intentional and non-teleological matter, to a very very stupid intentional homunculus, still requires some minimal intentionality. In short, there is a still an infinite distance between very very minimal intentionality, and ZERO intentionality.
V. Eliminativisim
Since all of the materialist theories of intentionality are lacking in many ways, several philosophers have suggested just dumping intentionality altogether. This view is called eliminative materialism. One of the more well known versions postulates that beliefs, desires, fears, thoughts, and so forth do not exist. There is only the brain's chemistry that can be described in neuroscientific terms, and that's it. Thoughts, beliefs, doubts, and the like, all intentional notions that are directed towards some target or subject, are a type of folk theory. Primitive peoples ascribe all sorts of intentional notions to nature, like the sea is angry about something, the sun desires sacrifices, or whatever. The same for astrology, magic, and the like. These are all folk theories, which modern science has refuted. So, ascribing beliefs, desires, anger, fear, pain, and so forth to human beings is similar to astrology and folk magic, and a future neuroscience, far from completion obviously, will also get rid of such notions from human beings.
The obvious problem with this is how science and reason can even operate, or how we can even have any knowledge at all, since these all rely on such intentional notions as beliefs, thoughts, and so forth. We all know we have doubts and beliefs and so forth, and the person who wants to convince us otherwise has quite the uphill battle. This theory may be similar to the solipsist, who wants to convince us, through only philosophical argumentation, that the external world does not exist. The solipsist's purely philosophical premises are stacked against our direct and every day experience of the external world. Clearly, the solipsist loses here. Similarly, the eliminative materialist stacks his purely philosophical premises against our direct and immediate experience of having beliefs, desires, and so forth, and so he may be on the losing side.
VI. Conclusion
So, to sum up, no materialist theory of intentionality has been successful so far. Conceptual role theories explain how a belief has a certain meaning in virtue of its neighboring beliefs, but doesn't explain how a belief can have any meaning at all in the first place. Causal theories say that meaning comes from connection with the outside world, but can't account for mistakes and the possibility of having beliefs that are not caused by the fact known. Biological theories explain our beliefs in terms of biological functions, but functions do not exist in the non-teleological world of Darwinian evolution. Dennet's instrumentalism explains meaning as being just a stance we take towards things, but cannot explain how meaning exists in the first place from meaningless matter. And finally, eliminativism, in saying that intentionality simply does not exist, may have the effect of making science and reason impossible, as these are all intentionality-laden tools.
So intentionality remains a puzzle for materialism of the mind, and whether a successful solution will be found or not remains to be seen.
I. Conceptual Role
Let's consider the possibility that something represents something else in virtue of the fact that it relates to other representations. So for example your thought about Mt Everest refers to Mt Everest because of its relationship to other neighboring thoughts, such as "mountains are large landforms" and "the Himalayas are a mountain range in China and Nepal", and so forth. So a thought represents something by being in context with other thoughts that also represent things. This web of representations, each
The obvious question is that, while this nicely explains how a thought has a specific meaning, it doesn't explain how anything has any meaning at all. All these other thoughts also have meaning, and if they get their meaning from the context of other thoughts, then you go to infinity and never end up explaining how any thought has any meaning at all in the first place.
The answer is that these thoughts rest on a Background of non-intentional capacities for acting with the world. At the foundational level, there is, for example, the behavioral capacity for climbing a mountain, and this forms the foundation of the thoughts and beliefs having the meaning that they do.
The problem with this is that there is a fundamental difference between motion, and intentional acting. A rock rolling down a hill is not intentional action; it's just matter in motion. An unconscious behavior, such as fleeing from a predator, is an intentional action since it is directed towards a specific end. So the behavior at the bottom level would still be intentional, if it is to explain anything, and so it leaves intentionality still unreduced.
II. Causal
An improvement of this theory is to recognize that for a thought to represent something else, it must connect somehow with the external world. So if there is a constant conjunction between an external stimulus, such as the vision of Mt Everest, along with the internal brain event that processes it, then eventually the thought or brain event will come to represent its referent.The external stimulus is causing the thought to point to something.
This theory is appealing but has several problems.
The first problem is that it can't account for misrepresentation. You might have a thought about Mt Everest, but in fact be mistaken and your thought is really about the neighboring mountain Lohtse, because it is at night and conditions are bad and you are mistaken. So in this case your thought about Mt Everest is caused, not by Mt Everest, but by Lohtse.
This further raises yet a further problem. If Mt Everest or Lohtse-at-night can cause your thought about Mt Everest, then why should the thought be considered a thought about [Mt Everest], rather than a thought about [Mt Everest or Lohtse-at-night]? Why does Everest get to win and be what the thought is about? A possible response to this is to say that the stimulus, Mt Everest, normally causes the thought, but other stimuli are parasitic on it, such as Lohtse-at-night. The second thought, caused by Lohtse-at-night, would not exist without the "parent" thought, caused by Mt Everest.
But there are even more problems.
Your thought about Mt Everest might be caused, not by Mt Everest, but by hallucinogenic drugs, or by the Matrix. Perhaps we live in the Matrix and there is no actual Mt Everest, in which case your thought about it was not caused by it at all, because it doesn't even exist. Your thought about Mt Everest was caused instead by computer software input directly into your brain from the Matrix.
Also, this theory explains why a certain thought has a certain meaning rather than some other meaning, but it doesn't explain how thoughts can have any meaning at all in the first place.
And finally, there is yet another problem with the causal account. There is a long causal chain, from the stimulus that is the object of thought all the way to the brain processes. The light photons travel from the sun, hit the snow of Mt Everest, travel through the air, into the eyes, where they cause electrons to travel up the optic nerve to the visual cortex, where they cause other brain processes, and so on. This is one long chain of causal processes, with Mt Everest at one end and the thought that represents Mt Everest on the other. Yet, if we remove what we already know to be the two end points of this causal chain, and just look at it in purely materialistic terms, we just have one long causal chain with no specific end points that are objective. If the photons from the sun are A, the travel through the air is B, Mt Everest is E, travelling through the air from the mountain to our eyes is F through M, entering our eyes is N, hitting our retinas is O, travelling through our optic nerve is P, and so on, then there are no objective endpoints. And so we would have to bring in another mind to say that T represents E, rather than M representing F. And bringing in another mind to assign meaning is once again to leave mind, and representation, unreduced and unexplained.
III. Biological Semantics
So if both these theories leave much to be desired, let's turn instead to biological theories of intentionality. We could think of representations and intentionality as biological functions, designed by natural selection. The need to run away from predators is a biological function, and perhaps over time this function becomes a representation. Of predators, say.
This theory avoids the misrepresentation problem. In this case, your thought that represents bears is caused, not by bears themselves, but by the desire to avoid bears. So therefore if you mistakenly believe that an old stump is a bear, this can be explained as a result of your representation being caused by the desire to avoid predators.
One problem with this theory is that it can't account for sophisticated and abstract beliefs and thoughts. Concerning math, philosophy, or other high level reasoning. Natural selection wouldn't be able to program such functions in.
Biological theories of intentionality also can't deal with the disjunction problem. If your desire to avoid both bears and stumps-that-look-like-bears has been wired in by evolution, then your thought that represents bears would actually represent bears or stumps-that-look-like-bears, not bears specifically.
Some philosophers, in response to this, suggest that this is not a problem with this theory. That in fact thoughts do not have exact meaning, and there is no specific fact of the matter about what any particular thought is. But this seems wrong. When you think about Mt Everest, there is a specific thing you are thinking about: Mt Everest. There is a specific object of your thought. Your thought about Mt Everest isn't a thought about "maybe Mt Everest, maybe Lohtse, maybe chocolate milk, whatever". It's about a specific object, or referent. However, even if we accept that our thoughts are not about specific referents, and accept the biological theory of intentionality, there remains yet another problem with it.
If the theory can explain why certain thoughts have certain meanings, but to explain why any thought has any meaning at all in the first place, it has to appeal to biological functions. Behavior directed at specific ends, or goals, or aims. But the whole point of Darwinian evolution is that it explains life without having to refer to functions, purposes, teleology, and such. The function of the stomach is not to digest food. The stomach causes the digestion of food, but it has no function. But if intentionality, or the meaning of thoughts, is to be explained in terms of biological function, then this theory illegitimately brings in teleology, which is anathema to materialistic theories.
IV. Instrumentalism
So let's look at a final materialist theory of intentionality.
We could take several different positions towards various things. If we need to know how to move an elephant, we need to know it's weight, size, and so on. So we could take the physical stance towards it. If we need to know what the elephant's heart does, we can take the design stance. We can AS IF the heart were designed for a particular function: pumping blood. Even though it wasn't designed. And finally, if we need to understand elephant behavior, we can act AS IF the elephant were consciously aware of its behavior. If the elephant trumpets to warn its herd of a predator, we can act AS IF the elephant were consciously deciding to do so rather than just acting on blind instinct. This is called the "intentional stance." We ACT LIKE the elephant is figuring things out mentally, and has intentionality, but really it doesn't. Or think of a DVR. We can take the intentional stance towards it, speaking about it as if it "knows" our favorite shows and is "smart enough" to record them, even though we know it isn't really.
So this theory says that our own intentionality reduces to just that: we act AS IF we have intentionality, but really we do not.
A few obvious problems pop up right away. For us to be taking a conscious "stance" towards anything presupposes intentionality. If our minds were not really directed towards specific targets or goals, then we couldn't take any stance towards anything.
A possible reply is that a subprocess in the mind assigns intentionality to thoughts. This is called a "homunculus". A little mind inside your mind. And then we would need to explain the intentionality of the homunculus by postulating another homunclus inside his head, and so on. Normally, this would lead to an infinite regress and thus a non-explanation, but philosopher Daniel Dennet proposes stupider and stupider homunculi, until we get down to the bottom level of no homunculi at all. But to bridge that gap, from no homuncli to the first, and stupidest, homunclus, is not just a wide gap but an uncrossable one. For, to leap from non-intentional and non-teleological matter, to a very very stupid intentional homunculus, still requires some minimal intentionality. In short, there is a still an infinite distance between very very minimal intentionality, and ZERO intentionality.
V. Eliminativisim
Since all of the materialist theories of intentionality are lacking in many ways, several philosophers have suggested just dumping intentionality altogether. This view is called eliminative materialism. One of the more well known versions postulates that beliefs, desires, fears, thoughts, and so forth do not exist. There is only the brain's chemistry that can be described in neuroscientific terms, and that's it. Thoughts, beliefs, doubts, and the like, all intentional notions that are directed towards some target or subject, are a type of folk theory. Primitive peoples ascribe all sorts of intentional notions to nature, like the sea is angry about something, the sun desires sacrifices, or whatever. The same for astrology, magic, and the like. These are all folk theories, which modern science has refuted. So, ascribing beliefs, desires, anger, fear, pain, and so forth to human beings is similar to astrology and folk magic, and a future neuroscience, far from completion obviously, will also get rid of such notions from human beings.
The obvious problem with this is how science and reason can even operate, or how we can even have any knowledge at all, since these all rely on such intentional notions as beliefs, thoughts, and so forth. We all know we have doubts and beliefs and so forth, and the person who wants to convince us otherwise has quite the uphill battle. This theory may be similar to the solipsist, who wants to convince us, through only philosophical argumentation, that the external world does not exist. The solipsist's purely philosophical premises are stacked against our direct and every day experience of the external world. Clearly, the solipsist loses here. Similarly, the eliminative materialist stacks his purely philosophical premises against our direct and immediate experience of having beliefs, desires, and so forth, and so he may be on the losing side.
VI. Conclusion
So, to sum up, no materialist theory of intentionality has been successful so far. Conceptual role theories explain how a belief has a certain meaning in virtue of its neighboring beliefs, but doesn't explain how a belief can have any meaning at all in the first place. Causal theories say that meaning comes from connection with the outside world, but can't account for mistakes and the possibility of having beliefs that are not caused by the fact known. Biological theories explain our beliefs in terms of biological functions, but functions do not exist in the non-teleological world of Darwinian evolution. Dennet's instrumentalism explains meaning as being just a stance we take towards things, but cannot explain how meaning exists in the first place from meaningless matter. And finally, eliminativism, in saying that intentionality simply does not exist, may have the effect of making science and reason impossible, as these are all intentionality-laden tools.
So intentionality remains a puzzle for materialism of the mind, and whether a successful solution will be found or not remains to be seen.
Monday, March 19, 2012
Introduction to Intentionality #1: The Problem Stated
The mind is often distinguished from matter in virtue of the fact that it has or seems to have several properties that are not present in physics. This is what leads to dualism, and if dualism fails, then at least some interesting challenges to materialism. The two big ones are qualia, the subjective look and feel of things, and intentionality, or meaning. This article will take a look at intentionality.
I. To Point, or Aim
The word "intentionality" means to point, aim, or direct towards some target, goal, or end. A better English word for it might be "aboutness": when something is about something else. We could also call it "meaning". When something has a meaning, it points to a specific end or target.
To take a few examples:
II. Peculiar
There are some peculiar aspects of intentionality that make it a complicated relationship. The relationship between pointer and referent does not need to involve any spacial distance. A thought or diagram of a "Betelgeuse" does not matter how close or far it is to the actual referent. Also, one can entertain two contradictory thoughts about the same referent. For example, "I believe the morning star is shining", and "I believe the evening star is not shining." The morning star and evening star are the same referent, and yet it is possible to have two different and contradictory thoughts about it at once, if you are not aware that they are the same object.
In addition, thoughts, words, pictures and so on can be about things that don't even exist, such as Santa Claus, or perpetual motion machines.
So this relationship between pointer and referent is a bit more complicated than a simple physical relationship between two items, and presents some interesting puzzles for the materialist who wants to say that mind is just matter and nothing more than that.
III. Problems for materialism?
We can look at a few quick reasons to think that intentionality is not a physical property, at least at first glance. For one thing, how can there even be a physical relationship between a pointer and a thing that does not even exist, such as perpetual motion machines? How can there be a physical relationship between a pointer and every object of a certain class, such as a thought about "atoms" in general? The thought points to every atom in the universe that has ever existed or will ever exist, so how can this relationship possibly be physical?
Another reason to suspect the impossibility of a physical explanation of intentionality is to just look at several of our earlier examples:
IV. But what about computers? Computers are material systems that represent things!
Computers are often offered as an example of a material system that refers to things all the time, and we are not tempted to be dualists with respect to computers.
But is that right? Take an abacus. On an abacus, the beads to the right represent the ones digits, the next column of beads represents the tens digits, and so on. But we assign this meaning to the beads. The beads don't actually mean anything. They are just collections of quarks and electrons, whose negative charges repel the electrons in the stick and keep the bead in its column. The bead doesn't refer or point to the number 1, or anything else.
Computers are different in degree but not in kind from an abacus. The computer's display is in English words, or numerals, which again are created and given that meaning by us. Without our application of meaning to it, the words and numbers on the screen are just meaningless electrons that have nothing to do with anything. Or think about what is happening inside the computer. Electricity is pulsing in on/off patterns, which mean 1 and 0, the language of computers. But just like with the abacus, we assign this meaning to the pulses of electricity. An "on" pulse of electricity doesn't mean 0, or 1, or 2, or hotdog, or anything else. It's just a group of electrons moving along a wire. We choose to apply a certain meaning to it, saying that a pulse of electrons means "1", and an absence of a pulse of electrons means "0."
V. Mind is different
But now think about the human mind. Your thoughts represent things. They point to a referent. So if materialism is true, then your thought about Mt Everest would consist of a certain configuration of electrons, neurons, dendrites, and so forth in your brain. Just physical particles and nothing more. But unlike a computer or an abacus, no one is assigning meaning to those particles. So how can meaningless particles point to something without any other mind applying meaning to them, as we do with computers?
If we want to say that some sub-process in the brain assigns meaning to our thoughts, then this just moves the problem back a step without solving it. If a sub process is responsible for assigning meaning to the electrons in our heads, then we have to explain how that sub process can assign meaning. This is often called a "homunculus." A little man inside your head is doing the processing, but to explain how he can think and assign meaning to things means we have to postulate yet another little man inside his head, and so on to infinity. This is of course an indication that that solution is not viable.
VI. The problem stated
So that is the basic problem of intentionality, and the problems that materialism has to overcome in order to try to explain it.
I. To Point, or Aim
The word "intentionality" means to point, aim, or direct towards some target, goal, or end. A better English word for it might be "aboutness": when something is about something else. We could also call it "meaning". When something has a meaning, it points to a specific end or target.
To take a few examples:
- The word "dog" refers to, or points to, it's referent: actual dogs.
- An arrow literally points to whatever it's intended referent is, such as a specific direction on a road.
- A picture points to it's subject matter.
- A thought about Mt Everest points to it's referent: Mt Everest
II. Peculiar
There are some peculiar aspects of intentionality that make it a complicated relationship. The relationship between pointer and referent does not need to involve any spacial distance. A thought or diagram of a "Betelgeuse" does not matter how close or far it is to the actual referent. Also, one can entertain two contradictory thoughts about the same referent. For example, "I believe the morning star is shining", and "I believe the evening star is not shining." The morning star and evening star are the same referent, and yet it is possible to have two different and contradictory thoughts about it at once, if you are not aware that they are the same object.
In addition, thoughts, words, pictures and so on can be about things that don't even exist, such as Santa Claus, or perpetual motion machines.
So this relationship between pointer and referent is a bit more complicated than a simple physical relationship between two items, and presents some interesting puzzles for the materialist who wants to say that mind is just matter and nothing more than that.
III. Problems for materialism?
We can look at a few quick reasons to think that intentionality is not a physical property, at least at first glance. For one thing, how can there even be a physical relationship between a pointer and a thing that does not even exist, such as perpetual motion machines? How can there be a physical relationship between a pointer and every object of a certain class, such as a thought about "atoms" in general? The thought points to every atom in the universe that has ever existed or will ever exist, so how can this relationship possibly be physical?
Another reason to suspect the impossibility of a physical explanation of intentionality is to just look at several of our earlier examples:
- The word "dog" refers to, or points to, it's referent: actual dogs.
- An arrow literally points to whatever it's intended referent is, such as a specific direction on a road.
- A picture points to it's subject matter.
IV. But what about computers? Computers are material systems that represent things!
Computers are often offered as an example of a material system that refers to things all the time, and we are not tempted to be dualists with respect to computers.
But is that right? Take an abacus. On an abacus, the beads to the right represent the ones digits, the next column of beads represents the tens digits, and so on. But we assign this meaning to the beads. The beads don't actually mean anything. They are just collections of quarks and electrons, whose negative charges repel the electrons in the stick and keep the bead in its column. The bead doesn't refer or point to the number 1, or anything else.
Computers are different in degree but not in kind from an abacus. The computer's display is in English words, or numerals, which again are created and given that meaning by us. Without our application of meaning to it, the words and numbers on the screen are just meaningless electrons that have nothing to do with anything. Or think about what is happening inside the computer. Electricity is pulsing in on/off patterns, which mean 1 and 0, the language of computers. But just like with the abacus, we assign this meaning to the pulses of electricity. An "on" pulse of electricity doesn't mean 0, or 1, or 2, or hotdog, or anything else. It's just a group of electrons moving along a wire. We choose to apply a certain meaning to it, saying that a pulse of electrons means "1", and an absence of a pulse of electrons means "0."
V. Mind is different
But now think about the human mind. Your thoughts represent things. They point to a referent. So if materialism is true, then your thought about Mt Everest would consist of a certain configuration of electrons, neurons, dendrites, and so forth in your brain. Just physical particles and nothing more. But unlike a computer or an abacus, no one is assigning meaning to those particles. So how can meaningless particles point to something without any other mind applying meaning to them, as we do with computers?
If we want to say that some sub-process in the brain assigns meaning to our thoughts, then this just moves the problem back a step without solving it. If a sub process is responsible for assigning meaning to the electrons in our heads, then we have to explain how that sub process can assign meaning. This is often called a "homunculus." A little man inside your head is doing the processing, but to explain how he can think and assign meaning to things means we have to postulate yet another little man inside his head, and so on to infinity. This is of course an indication that that solution is not viable.
VI. The problem stated
So that is the basic problem of intentionality, and the problems that materialism has to overcome in order to try to explain it.
Sunday, March 18, 2012
Introduction to Dualism #1: Plato
Plato was the oldest defender of dualism, the view that mind is a different fundamental substance than matter. While his evidence for dualism is not take very seriously anymore, he does have a few interesting points worth exploring.
I. Theory of Forms
One of the central pillars in Plato's philosophy is the theory of Forms. To illustrate this, let's use the example of a triangle. Any physical triangle, such as one drawn on a computer screen, will be less than perfect. The lines will have thickness and thus be more like really skinny rectangles. The lines will be jagged from the pixels. On a microscopic level, they will not be perfectly straight. So any physical triangle can only be a rough approximation of that perfect archetype triangle, what Plato would call the Form of Triangle. The perfect triangle cannot be physical. As a result, the physical world is just a rough approximation of the real world, which is the non-physical realm of abstract Forms. In other words, the realm of pure knowledge is the real world.
So on Plato's view, after death the soul is liberated from the human body and can have direct access to the Forms. So why does Plato think the human soul is separate from the body?
II. The Argument from Opposites
Plato says that when things become a certain way, they become that way from their opposites. If you become taller, it is because you were shorter. If you wake up, it's because you were asleep. And death comes to be only from life, and in that case then life only comes to be from death.
III. The Argument from Recollection
Plato shows how people know the Forms without having to learn about them, and so therefore must have lived before they were born. For example, people can compare two sticks and know that they are unequal, without ever having to learn what Equality is. Therefore, people already know the Form of Equality without ever having to learn about it.
IV. The Argument from Affinity
Destruction occurs in objects that are composites of many parts. The body, being composed of parts, can be destroyed. But the human mind is simple and not composed of parts. Therefore, it cannot be destroyed.
V. Objections
This version of dualism is not all that well supported. There are many examples of things not coming from opposites, or not returning to opposites. Age comes from youth but youth does not come from age. In addition, the arguments depend on Plato's Theory of Forms, which is contentious at best.
I. Theory of Forms
One of the central pillars in Plato's philosophy is the theory of Forms. To illustrate this, let's use the example of a triangle. Any physical triangle, such as one drawn on a computer screen, will be less than perfect. The lines will have thickness and thus be more like really skinny rectangles. The lines will be jagged from the pixels. On a microscopic level, they will not be perfectly straight. So any physical triangle can only be a rough approximation of that perfect archetype triangle, what Plato would call the Form of Triangle. The perfect triangle cannot be physical. As a result, the physical world is just a rough approximation of the real world, which is the non-physical realm of abstract Forms. In other words, the realm of pure knowledge is the real world.
So on Plato's view, after death the soul is liberated from the human body and can have direct access to the Forms. So why does Plato think the human soul is separate from the body?
II. The Argument from Opposites
Plato says that when things become a certain way, they become that way from their opposites. If you become taller, it is because you were shorter. If you wake up, it's because you were asleep. And death comes to be only from life, and in that case then life only comes to be from death.
III. The Argument from Recollection
Plato shows how people know the Forms without having to learn about them, and so therefore must have lived before they were born. For example, people can compare two sticks and know that they are unequal, without ever having to learn what Equality is. Therefore, people already know the Form of Equality without ever having to learn about it.
IV. The Argument from Affinity
Destruction occurs in objects that are composites of many parts. The body, being composed of parts, can be destroyed. But the human mind is simple and not composed of parts. Therefore, it cannot be destroyed.
V. Objections
This version of dualism is not all that well supported. There are many examples of things not coming from opposites, or not returning to opposites. Age comes from youth but youth does not come from age. In addition, the arguments depend on Plato's Theory of Forms, which is contentious at best.
Thursday, August 4, 2011
Dualism
Mind is different from matter:
Qualia
The mind has private experiences. You can watch someone wince in pain, and even see the brain activity on an MRI, but you can never experience their actual experience. This is qualia; the privacy of personal experience. Material things are public and can be observed. The mind is private and can only be observed from a first person perspective.
Indivisibility
The mind cannot be divided into parts, like material things can. Multiple Personality Disorder is a case of another mind in the same body, not the mind splitting up into two. MPD might not even really exist, as many cases have been exaggerations or hoaxes. Split brain cases may be a case of mind splitting, but evidence shows that it might not be so much a case of one mind splitting into two as much as just an “absence of mind” type of phenomenon, that anybody experiences from time to time.
Conceivability
If two things are identical, then it is logically impossible to have the one without the other; it isn’t even coherent to imagine the one without the other. You can’t imagine water without H20; they are identical. But it seems that we can coherently imagine mind without brain: imagine yourself disembodied, for example. It is at least logically coherent, even if not physically so. This indicates that they are not identical.
This argument requires “rigid designators”, or words that refer to the same thing no matter what. Neil Armstrong is identical with the first person to walk on the moon, but there is a possible world where someone else walked on the moon first. Hence, the two are identical in our world, but “first person to walk on the moon” is not a rigid designator; it could have been anybody. H20 and water, on the other hand, are in fact rigid designators. So are “my mind” and “my brain.” Yet, it’s logically possible to have “my mind” without “my brain.”
Another possible problem with this argument is that perhaps we can’t really imagine our minds disembodied at all, like we think we can. When light bounces off an object, the photons go into your eyes and cause the sensation of sight; but if you are disembodied, what happens? The photons bounce off the object and go to nowhere. So perhaps you can’t really imagine yourself disembodied like you thought you could. On the other hand, take away the sight and you still have a thinking person, and hence the argument may still work.
Interaction Problem
The main argument against dualism is: how can something non-physical interact with something physical? No mechanism has been forthcoming. Also, the interaction problem implies that energy would have to come from somewhere else (because the mind is non-physical, but interacts with the physical), and this is against the laws of thermodynamics. This does not necessarily refute dualism (if the arguments work, then so much the worse for physics), but it is a huge problem. There are a few answers to this problem.
Qualia
The mind has private experiences. You can watch someone wince in pain, and even see the brain activity on an MRI, but you can never experience their actual experience. This is qualia; the privacy of personal experience. Material things are public and can be observed. The mind is private and can only be observed from a first person perspective.
Indivisibility
The mind cannot be divided into parts, like material things can. Multiple Personality Disorder is a case of another mind in the same body, not the mind splitting up into two. MPD might not even really exist, as many cases have been exaggerations or hoaxes. Split brain cases may be a case of mind splitting, but evidence shows that it might not be so much a case of one mind splitting into two as much as just an “absence of mind” type of phenomenon, that anybody experiences from time to time.
Conceivability
If two things are identical, then it is logically impossible to have the one without the other; it isn’t even coherent to imagine the one without the other. You can’t imagine water without H20; they are identical. But it seems that we can coherently imagine mind without brain: imagine yourself disembodied, for example. It is at least logically coherent, even if not physically so. This indicates that they are not identical.
This argument requires “rigid designators”, or words that refer to the same thing no matter what. Neil Armstrong is identical with the first person to walk on the moon, but there is a possible world where someone else walked on the moon first. Hence, the two are identical in our world, but “first person to walk on the moon” is not a rigid designator; it could have been anybody. H20 and water, on the other hand, are in fact rigid designators. So are “my mind” and “my brain.” Yet, it’s logically possible to have “my mind” without “my brain.”
Another possible problem with this argument is that perhaps we can’t really imagine our minds disembodied at all, like we think we can. When light bounces off an object, the photons go into your eyes and cause the sensation of sight; but if you are disembodied, what happens? The photons bounce off the object and go to nowhere. So perhaps you can’t really imagine yourself disembodied like you thought you could. On the other hand, take away the sight and you still have a thinking person, and hence the argument may still work.
Interaction Problem
The main argument against dualism is: how can something non-physical interact with something physical? No mechanism has been forthcoming. Also, the interaction problem implies that energy would have to come from somewhere else (because the mind is non-physical, but interacts with the physical), and this is against the laws of thermodynamics. This does not necessarily refute dualism (if the arguments work, then so much the worse for physics), but it is a huge problem. There are a few answers to this problem.
Occasionalism
God sees that the phone rings, and simultaneously causes you to have the sensation of the phone ringing.
Parallelism
God set everything in motion at the beginning of time, like synced clocks. You receive the sensation of the phone ringing at the same time that the phone rings because the two have been timed to happen simultaneously from the beginning.
Epiphenominalism
The mind is a byproduct of physical processes, like smoke is the byproduct of fire. There is only a one-way causal connection. Your physical body does what it does, and your mind is just along for the ride. The problem is you could never affirm your mental state, such as your belief that epiphenominalism is true, because your mind has no causal power over your lips.
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