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6.3: Idealism and Monism-Materialism

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    Metaphysical View of Idealism

    Things are composed of

    1. Sensible properties and
    2. Matter


    Matter was seen as necessary for differentiating one object from another. Suppose you had two objects with the same properties:

    • a list of the properties of both would be identical.
    • how would you know that you had two objects?

    Matter itself had no properties of its own.


    Problem with Matter:

    According to Bishop Berkeley, once you took away all of the sensible properties of a thing, you should be left with the bare matter. If it has no properties of its own, how would you know it? This led him to conclude that a thing is nothing more than its sensible properties. Things are nothing but their properties:

    • Get three buckets of water, one at room temperature, one that is as hot as you can stand it, and the third must be very cold (put in ice).
    • Hold your right hand in the pail of hot water and your left hand in the pail of cold water for about 3 minutes.
    • Then, place both hands in the bucket of room temp water.
    • How does the water feel to the right hand?
    • How does the water feel to the left hand?
    • Aha! What can we conclude from this experiment?
    • The "hotness" or "coolness" of the water is not in the water.
    • So where is the sensation of "hotness" or "coolness" existing?
    • In your mind?

    Idealism says that:

    • if the sensible properties of things exist in the mind (not in the things themselves).
    • and things are nothing more than bundles of sensible properties, then...
    • things must exist in the mind only (as ideas).
    • similarity of perception (of objects): why do things seem the same to all of us
    • persistence of objects: do things continue to exist when no one is perceiving them
    • problem of other minds: how do I know other minds exist?
    Similarity of perception:

    Question: Why do things appear the same to all of us if they are just bundles of ideas in our (individual) minds?

    Answer they might not - the wall may be "blue" because we have all been taught to call it that, not because it really is "blue"

    Persistence of objects:

    Questions: Do things continue to exist when no one is looking at them? Does the floor outside the room still exist? Does your car still exist in the parking lot?

    Answer 1: Well, someone is out there right now "seeing" it - this keeps it in existence until i get back. But what if no one is out there right now?

    Answer 2: Someone always is "seeing" all the things in the world at once. Couldn’t that be God?

    • Persistence of objects and similarity of perceptions
    • Both can be explained by positing an all-knowing (all-seeing) God.
    • Idealists use God to explain how these things continue to exist.
    • They are as they are because God perceives them.
    The problem of other minds:

    Dualist response -

    • Best explanation for what we see in the behavior of others
    • Biological similarity between bodies makes it even stronger.
    • But - in idealism there is no such physical similarity
    • Only way to connect the two is to posit some sort of spiritual similarity.

    Because of the lack of evidence for other minds, and because of the (supposed) lack of any perceptive faculty by which we can know God (who is needed to solve other problems) idealism will not work as an explanation of how mind and body interact.


    So now we arrive at the real challenge to the dualist view and the solution to the mind-body problem that is attracting more and more adherents. In this view there are no minds at all. At least there are no minds separate from the brain. There are no non-physical entities. The mental activities are accounted for in terms of the brain and what it does. There are a variety of approaches to explaining the mind in terms of the brain. This approach is a form of monism for it claims or assumes that there is but one substance: matter. It is a physicalism.

    Physicialist View of the Mind

    There will be a great deal of material here. It is put here to challenge your belief that you have a mind. More and more people are coming to think differently. The belief in a mind has been held by so many and for so long that it takes some doing to demonstrate that perhaps it just is not true.

    The claim is made that there is no non-physical mind. All that we do and experience is accounted for in physical terms. When the day comes that humans interact with a very well made and very complex computer, perhaps in the form of a human body, a robot-android, and the humans cannot tell that it is a silicon based form of activity then humans will realize that they are not really different from the robot. Humans are a carbon-based life form. The android-robot will be a silicon-based life form. If humans and androids both act alike and speak of "feelings" and "thoughts" and so forth then humans will know that the mind is just another name for the physical brain. So, the views presented here will quickly get to the cases of computers and robots as a means of offering proof of the non-existence of a non-physical mind.

    Future of Robotic Artificial Intelligence

    What is there really that you or a human being does that indicates that they have this non-physical entity associated with the behavior. Robots can be programmed to speak, to write, to calculate, to learn and even to make other robots (first step successful in the year 2000). Robots, androids, can be made to speak of feelings and to report that when for example fluid intake over 4 hours drops below 50 cc to say, "I'm thirsty" or some other appropriate phrase. The android could be programmed to say what the humans say when fluid intake drops to a low point. Is there anything more to "feeling thirsty" than that? As the behaviorist, B.F. Skinner, claims, we know that someone is thirsty because they drink. We should not think that they drink because they are thirsty. Neurologists have been busy at work identifying the locations in the brain responsible for memory, speech, creativity and motor control as well as anger, depression and even love, both the physical attraction stage and the "romantic" stage. There have been numerous examples of people who have had their basic behavior change as a result of brain injuries, illnesses and chemical imbalances. With all of this mounting evidence there are many people who believe that there are no non-physical minds, that we have only brains.

    Variations on the materialist position

    • Behaviorism
    • Logical behaviorism
    • Semantic behaviorism
    • Folklore
    • Functionalism
    • Structuralism


    As used in the philosophy of science, physicalism is the view that all factual knowledge can be formulated as a statement about physical objects and activities. Thus, the language of science can be reduced to third person descriptions.

    The positivists defined the physical as that which can be described in the concepts of a language with an intersubjective observation basis. This could be called unity of science physicalism. It is the primary meaning of physicalism in the philosophy of Science. Another type of physicalism might be called causal physicalism, the view that all causes are physical causes.

    There is a lot of confusion in the philosophy of mind literature stemming from a tendency to take physicalism and materialism to be interchangeable.


    Some psychologists believe that they can account for all of human behavior in terms of operant conditioning. All that a human does (including ideas and feelings) are behaviors that can be explained in terms of basic physical factors:

    • genetic inheritance
    • physical drives
    • individual human history of interactions
    • conditioning-learned behavior patterns

    There is no essential difference between a human and any other mammal. Humans use language according to what they were reinforced for saying or writing. There is no mind. There is only the brain as with any other mammal. Human thought is simply brain behavior (activity) that has been learned (reinforced) and associated with some stimuli and evoking some response.

    Logical Behaviorism

    The word "mind" is the result of a mistake, an error in logic. If a person arrived on the campus of a large college or university and asked someone in the parking lot, "where is the college?" that person might point out one building after another saying something like: "well that's the administration building over there." "That's the gym building way down there." That's the new Science building over there." then the visitor interjects with "no, I want to know where the college is?" Well the visitor is making the mistake of thinking that the college is a specific place as are the buildings, instead of the college being a name for the entire collection of buildings, programs, instructors, students etc... The visitor is making an error. Well, in like manner the word mind has been mistaken for a thing when it is just a name for a collection of activities of the brain.

    Semantic Behaviorism

    Holders of this view believe that the word mind has been improperly associated with the existence of an entity that exists apart from the body, the brain. Those who speak of the mind as if it were a non-physical entity have been reinforced in this inappropriate behavior and incorrect association.


    All talk of the mind as distinct from the brain originates from an earlier time when people were not as well informed as we are today. Most people have had to abandon thinking of many things that were part of the old folklore, such as:

    1. The earth is flat
    2. The earth is at the center of the universe
    3. The sun moves
    4. The moon is a goddess
    5. Lightning is sent by superhuman beings from above


    The mind is really the name given to the collection of brain functions. The mind is what the brain does; we are (very sophisticated) biological machines. According to functionalism, 'mind' refers to the brain's activity of thinking; the mind is not a special kind of thing or substance--not a spiritual thing or a physical thing--but rather a certain kind of activity that is carried out by a physical thing, in the case of humans, by the brain.

    Analogy #1: other bodily functions

    Digestion is what the stomach does. Circulating the blood is what the heart does. Cleansing the blood is what the kidneys do. Thinking is what the brain does.

    Some machines can do the job of our organs when they fail. Artificial organs are growing more common (cornea implants, kidney machines, and artificial hearts). If thinking is simply the function performed by the brain, it might someday be possible to replace parts of the brain (maybe even the whole brain) With artificial parts. But what does the brain do?

    The brain processes information gathered by the senses and stored in memory. The outputs of this processing include the things we say, think and do. In effect, thinking is a form of computation. The mind is to the brain as software is to hardware.

    Two important considerations have added plausibility to this view of the mind.

    Computers can be made of almost anything.In principle, it is possible to build a computer out of almost anything. Early electronic computers were made with vacuum tubes. Current computers are made with transistors and silicon chips. Any device that can be used to "read" and "write" from a "tape" on which are symbols that represent "1's" and "0's" can be used to build a computer. In 1833 Charles Babbage conceived a design for a mechanical computer made from interlocking gears and levers. He called his computer "the analytical engine." the problem with using mechanical components is that computers made from them perform their computations so slowly, they are practically useless.

    Nature, however, found a way to build a computer using biological components, without silicon chips and transistors. We call it the brain.

    Levels of Explanation for Psychology

    Psychology started out as the study of the mind, and by "mind," most early psychologists meant something like the Cartesian soul. When souls fell from fashion, psychologists faced a problem: if there are no souls, and if neurologists study brains, what's left for psychologists to study?

    When behaviorism was "in" psychology became the study of behavior. But now behaviorism is "out," so what is psychology the science of? Today, psychology is the study of cognitive and other processes carried on in the brain. Who knows what it will be studying when that particular subject goes out of fashion.

    Levels of Explanation for Computers and Brains
    • Physical level: from one point of view (the engineer's) all that is going on in a computer is a series of electronic changes.
    • Design level: from another point of view (the programmer's) the machine is running a program.
    • Commonsense level: from our point of view (the user) the computer is word processing or solving an equation.
    • Physical level: from one point of view (the neuro-biologist) all that is going on in a brain is a series of chemical changes
    • Design level: from another point of view (the psychologist's) the brain is running a program.
    • Commonsense level: from our point of view (the user) the brain is thinking

    Thus, most psychologists are functionalists, the mind is to the brain as a program is to a computer. Is a thinking computer a possible thing? Since both computers and brains are computational/information processing devices, it should be possible, in principle, to build a computer that thinks.


    A computer can only do what it is programmed to do. We aren't programmed; we decide what we will do.

    • Computer program + input history = what the computer will do next.
    • Genetic make-up + experience = what you will do next.

    Your behavior is the product of the nature of your genes and the nurture of your experience. The computer's behavior is the product of the nature of its program and the nurture of its input. So what's the difference?

    So there are those who think that humans are just very complex organic machines, that humans are not essentially different from an organic computing device. When a computer is made that acts so much like a human that most people would not be able to tell that it was a computer then we shall know that humans do not have a non-physical mind or a non-physical soul but that we are hydro-carbon life forms that have complex information processing units (brains) that are capable of behavior indicating awareness.

    There are numerous works of science fiction and movies and television series that have had robots in human form, androids. These robots or thinking machines have been mistaken for being human or have acquired so many human traits as to be deemed worthy of being accorded human rights.

    Data Controversy Over Rights-Star Trek, Next Generation


    The mind is a name given to a collection of brain structures. Each mental event is accounted for in terms of the various arrangements and operations of parts of the brain.



    Materialism is another form of Monism: There is only one kind of substance in the universe and only material substance exists; there is no non-physical substance. This view had important implications for existence of god, soul, angels etc...There are 3 main points:

    1. Uniformity of (physical) laws
    2. Denial that there is “intelligent” purpose
    3. Denial of non-physical entities

    Uniformity of Law

    Physical laws are descriptive: they don’t say how it ought to be, but rather they describe how things actually behave. Physical laws describe a universe which operates according to regular, uniform laws.

    1. Every event has a cause
    2. Same causes under same conditions get same effects.

    Denial of Intelligent Purpose

    One challenge to materialism is that it must be able to explain “intentionality” of actions.

    • acts can serve a purpose - like blinking reflex
    • but acts occur because the laws of physics hold true - not because they are directed by someone.

    Denial of Non-Physical Entities

    Non-physical entities are proposed out of ignorance of the true nature of things. Once we realize that there are only physical causes for things, we will look for (and find) just those sorts of causes.

    • Where are they?
    • Can we spot such things?
    • Why do we need to suppose they exist?

    Brain As a Machine

    The mere act of catching an object thrown to us requires an enormous amount of processing power and speed.

    • calculate trajectory
    • moving to intercept object on its trajectory
    • coordinating grasping motions along with recovery from motion in 3 dimensional space.

    So what do we do with mentalistic terms?

    • Thought is a particular brain process
    • Mind is our collective awareness of our own brain processes
    • Memory is a physical process of information storage and retrieval
    • Dreaming is testing and establishing relationships between information stored in memory.

    Uploading Consciousness... Michio Kaku

    What is consciousness?

    Do we have consciousness because we are aware of it or are we aware of things because we possess consciousness? Why does it exist and, most importantly, how?

    The answers to all these questions are constantly debated in philosophy, especially philosophy of mind. When it comes to robotics and the expansion of technology towards A.I., these arguments focuses into the consequences and the treatment of the new perspectives humans would face if technology reaches the ability to produce robots that can develop consciousness. Some of the questions brought to awareness are of how would conscious androids be treated? Are they entitled to human rights, since they would possess, even if artificially, the same properties as human beings – feelings, awareness, consciousness, emotions? What to do if a conscious android wouldn’t fit into the expectations of its purpose? The first impulsive answer would be too simply “turn it off”, but think again: could it be considered murder, since you are “removing” life from a conscious being?

    Among the population, the idea of co-existing with conscious androids brings not only questions and concerns, but also fears. But what are we really afraid of? Are we afraid that they might become dangerous? That the androids may form an “army” and dominate humans, turning against their own “masters?" Or is it that we are not prepared to realize that humans may not be the last degree in the evolutionary scale we were always so proud and safe to dominate?

    The Singularity

    Singularity is the idea that machines could have the capacity to evolve at a faster pace than humans and is linked to the fear of robots gaining too much control.

    • materialism does not allow for spiritual entities:
    • no God, soul, angels, or devils.
    • idealism may lead us into a radical solipsism: the view that I am the only being in the world
    • yet, dualism cannot explain how the mind and body interact.
    More Conclusions

    If we as humans are just a form of organic machine, then:

    • is it possible to construct a non-organic machine which can do the same things?
    • could we create an artifact which was intelligent?
    • this will require that we know what intelligence is
    • it will also require that we understand how it is that humans are intelligent

    Philosophical Applications

    Gloria’s Near Death Experience

    “As I was lying on the table I heard the doctors pronounce the operation a failure and pronounce me dead. I then remember them frantically trying to resuscitate me. While they were trying to bring me back to life, I was just floating up near the ceiling. It was a weird feeling because I was up there and my body was below… Then I seemed to wander up through the floors of the hospital. I saw plainly, for instance, a young man who had been injured in an automobile accident… Then everything began to get dark: I passed through a spiraling tunnel until I seemed to come to a place illuminated by an immensely bright light… A tremendous peace overcame me. My grandmother, who had died 9 years before, was there. I couldn’t see her—for she seemed behind me—but I could feel her presence and hear her voice… Suddenly I was thrust back into my body. I don’t know how or why. My next recollection is of the nurse standing near me in the recovery room.”

    1. Does Gloria’s near-death experience convince you that mind and body are separate entities? Why or why not?
    2. If yes, can you think of further reasons that support the conclusions that Gloria’s mind had indeed left her body?
    3. What would you say to the researchers who claim that Gloria’s experiences were caused by neurological activity in the brain?

    Vocabulary Quizlet 6.3

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