mind, brain and self

PHIL 2160 - Mind, Brain and Self

with Professor Evan Thompson

Fall, 2003

These are more of a set of notes, than essay stuff. I wanted to keep them because it was a really interesting philosophy class and there was a lot to remember. It's the take-home final exam, so no cheating.

1. Explain the EGO THEORY and the BUNDLE THEORY of the self. Which do you think is rationally the stronger theory? Explain why. Be sure to explain both theories, evaluate both and then pick a side. You could also talk about split brains, the telecloner, multiple personalities, Multiple Drafts Model.

Ego Theory – I am a single continuous self who has experiences. I am a subject who makes my decisions etc. This is the most common way of looking at the question of the self. Most religions focus on the ego theory (except Buddhism). The soul is a continuing entity that is central to a person’s life and to their moral responsibility. As well as being able to survive the death of the physical body (not all ego theories state this). Most forms of substance dualism are ego theories because they equate the separate mind, or non-physical substance with the experiencing self. Extreme ego theories entail mysterious, untestable entities.

Bundle Theory – There seems that there is a single, continued self, but this is misleading. There is no underlying conscious or unitary self, and the illusion that there is must be explained in another way.

Buddhism rejects ego theory and Derek Parfit calls Buddha the first bundle theorist. Bundle theories take their name from David Hume who argued that we were not a self, but more of a bundle of perceptions or sensations. A person’s life is a series of sensations, experiences and ideas that are tied together with the aid of memory. Bundle theorists argue that there is no expiriencer.

Bundle theory is counter-intuitive. It is very difficult to imagine our selves not existing.

Multiple Personalities – Are there two, distinct personal selves? The idea of a multiple personality is the idea and concept of memory. There is an absence of memory when the other self is occupying.

Hypnosis became a very popular tool in studying multiple personality cases. Most of the cases of split personality were women who didn’t just seem to have a change in personality, but a distinct separate person that inhabited their body. Sometimes the person claims that not only are there more than one people in the body, but they could all be conscious at once, or experience the dreams of the others or not in control. This would seem to be a case of simultaneous consciousness. Ego theorists would be determined to find the real self and kill the other personalities in order to cure the person of nonpersonhood.

Some cases have shown that different personalitities can have different IQs, and EEGs.

Bundle theory can explain multiple personalities by saying that the mind of any human being is constituted by the discorses that they are involved in.

Split Brain – Ego theorists assume that the selves are countable things. There must either be one or two of them inhabiting a split-brain body.

Tests show that in a split brain patient, their iq, verbal and problem-solving skills are the same as well as their personality. But when the hemispheres were tested separately, there were dramatic changes.

The hemispheres were seen to act almost identically and independently when severed. This showed that it was possible that one hemisphere of the brain would be unaware of what the other half was doing. Also, that each hemisphere could remember what it was doing, but that the information was inaccessible to the other.

Many ego theorists argue that in a split brain case, there are two sparate streams of consciousness, or a dual consciousness – essentially, two people. Others argue that the left hemisphere acts as an interpreter, who makes beliefs and manipulates language, this is where high-level consciousness is. This is another ego theory. Where does this leave the less dominant half? With no sense of self?

Other experiments of split brain cases show how it is possible for the same body to play a game with the other side of his brain. Does this mean that he is the same person?

Ego theorists assume that selves are countable things; that there must either be one or two.

Bundle theorists like Parfit argue that there are two streams of consciousness, one seeing red and one seeing blue but there are not two conscious persons doing the seeing. But it doesn’t matter, because in bundle theories, the answer is that there is no selves to count.

2. How many persons are there in a split brain patient? One? Two? None? Explain and defend a) what is a split brain. b) what makes it interesting c) should we think of them as one self, two (in one body or unified, one for each hemisphere), no selves or misapplied like Dennett.

You can talk about ego and bundle theory in here as well.

a) What is a split Brain? Disconnected because of epilsepsy etc.

b) the hemispheres can act independently and can be unaware of what the other is doing while retaining memory of its own activity.

c) no self – misapplied. Not two or more. SEE ABOVE

3. Explain the teletransporter thought experiment. What is the point? Is it better described as a method of transportation or person duplication? Why? Is it an argument? What is involved with the continued existence of a self over time? What accounts for the continued ego over time? Bundle theory says that there is no absolute fact of the matter and this is presented well in the textbook.

The teletransporter would record your exact atomic structure and in turn destroys it, but reforms you somewhere else using spare atoms.

If you would go, you would say that you wouldn’t notice the difference. You would have the same memories and personality because your brain would constitute the same person. The person that says no, believes in a soul or that you would die because there is something dualistic about the mind and the body.

The bundle theorist would say that the question wouldn’t matter because it is empty. There is no self.

What if you were to replace neuron by neuron, at what point would there be a new person, or two people? If you think that there must be an answer, you are an ego theorist, meaning, there has to be a number. If you are a bundle theorist, it is meaningless.

4. Describe the Turing Test (both the imitation game and the total Turing Test). If a machine passed the unrestricted or total Turing Test, what would you conclude about the machine? Can it think or not? Is it conscious or unconscious? Why? This relates to the philosopher zombie.

The turing test is whether a computer could hold a conversation with a person and fool the person into thinking that it is a person. Requirements to pass the turing test: natural language processing, knowledge representation, automated reasoning, machine learning. The total turing test is the computer example, the imitation game.

This focuses on an objective notion of intelligence and avoids talk of internal processes and consciousness. He called his test the "Imitation game" but a modified version of it is known today simply as "the Turing test." He proposed a game played initially by three humans -- a man, a woman, and a judge of unspecified gender. At the start of the game the judge is in communication with the other two humans by teletype machine but can't see them and does not know which teletype machine is connected to which gender person. The judge has to determine the gender of the person at the other end by asking questions via the teletype machine. But both of the "players" are trying to convince the judge that they are female. The test of the computer is achieved by replacing the man with a computer. If the judge can't make the gender distinction any more successfully when a computer is imitating a man imitating a woman then the computer is said to have "passed" the test and to be intelligent. The modern version leaves out the gender question. Instead, the judge has simply to decide whether an entity of unknown origin at the other end of a computer connection is a human or a machine. If a machine is judged to be a human then it passes. (It's not clear what it means if a human is judged a computer.)

In his article Searle attacks a branch of AI known as "strong" AI. The central thesis of strong AI, also known as the computational hypothesis, is quite simple -- if we give a computer the appropriate program it will be intelligent, conscious, self-aware, feel emotions, etc. In the words of one strong AIer, our brains are "machines made of meat," and our "mind" is simply the right computer program. (Weak AI, on the other hand, only claims that computers can be useful in understanding our own intelligence.) Because Turing proved that all computers are equivalent, if our brain is a simply a computer running a program then, in theory, it would be possible to discover the program and translate it onto a electronic computer. Searle claims that intelligence is not simply a matter of computation or symbol manipulation. His argument is known as the Chinese Room argument, after the thought experiment he proposes in the article.

5.According to Dennett, there is no such thing as the exact moment of which you become conscious of something. What reasons does he give for this claim? Do you agree or not? Why?
Related to this is subjective referral, Libit Experiments, apparent motion, Stalinesque vs. Orwellian (the distinction is misleading), Multiple Drafts model, probing.
Go to the heart of the question without a summary of everything.

Multiple Draft Model – According to this model, all kinds of mental activities including perceptions, emotions and thoughts are accomplished in the brain by parallel, multitrack processes of interpretation and elaboration of sensory inputs, and are all under continuous revision.

This is in complete opposition to the Cartesian Theatre. It is called multiple drafts because there is no final edit, it is only revisions and revisions that is only accessable at the time you probe it.

At any point, there are multiple drafts or narrative fragments at various stages of editing in various places in the brain.

Multiple draft theory means that discriminations only have to be made once. There is no master descriminator that has the experience.

This is similar to the idea of a internet. Almost like a narrative stream that comes out when it is probed in some way. Some drafts are laid down, most fade away and some are used to control speech etc.

There is no show and no theatre or any fact of the matter.
The observer is like a narrative center of gravity. There are no fixed facts about the stream of consciousness independent of particular probes.

Libit Experiments – ½ a second of neuronal activity is needed for consciousness. He found that stimulating parts of the brain would bring about sensations i.e. brush on the arm. There is a minimum intensity that must be read and it must last for a certain duration. This term is called Neuronal adequacy.

Libit argues that sensory experiences are subjectively referred back in time once neuronal adequacy is reached. The subject gets referred back to when it actually happens.

Orwellian VS Stanlinesque – If you believe that there is a time at which visual experience becomes conscious, then you have two options.

The first is the Orwellin Revision theory that states the person can be conscious of something and then something else can come along and revise it.

Stalinesque revision theory states that the first image is never conscious, only it gets delayed into consciousness.

Dennett says that there is no way to find out so it is a meaningless question. Not only do we assume there is a real time that things happen in the brain, but a real time that they enter into consciousness.