Substance Dualism - Questions - PowerPoint Presentation

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Substance Dualism - Questions

Read through your answers again first.

Look at the feedback you’ve been given – where were you mistaken? What did you need to include to push yourself to full marks?

Make sure you are clear on any issues you had.

Get a pen that is a different colour to the one you wrote your answers in.

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1. What is meant by the term “Qualia”?

Most common mistake: Not linking definitions to mental states or conscious experience!“Qualia is the what-it-is-likeness of something”

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2. Leibniz’ Law

Most common mistake: Not stating that “two things” must have “all the same properties”“LL states that any things with the same properties are identical.”

Leibniz’s Law

(also called the Indiscernibility of

Identicals

):

If

two things have all the same properties, then they are the same

thing (they are identical).

Conversely, If two things do not have the same properties, they are not the same thing (not identical).

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3. Argument from Divisibility

Most common mistake: Not stating why minds can’t be divided but the physical can OR stating that the physical is extended and the mind isn’t but not saying why this is important.

I am indivisible.My body is divisible.Therefore I am not my body.

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Onto… Conceivability Argument

First, I know that everything which I clearly and distinctly understand is capable of being created by God so as to correspond exactly with my understanding of it. Hence the fact that I can clearly and distinctly understand one thing apart from another is enough to make me certain that the two things are distinct, since they are capable of being separated, at least by God. The question of what kind of power is required to bring about such a separation does not affect the judgment that they are distinct. Thus, simply by knowing that I exist and seeing at the same time that absolutely nothing belongs to my nature or essence except that I am a thinking thing, I can infer correctly that my essence consists solely in the fact that I am a thinking thing. It is true that I may have (or, to anticipate, that I certainly have) a body that is very closely joined to me. But, nevertheless, on the one hand I have a clear and distinct idea of myself, in so far as I am simply a thinking, non-extended thing; and on the other hand I have a distinct idea of body, in so far as this is simply an extended, non-thinking thing. And accordingly, it is certain that I am really distinct from my body, and can exist without it.

What argument is Descartes making here?

Can you split it into premises and conclusion?

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Conceivability Argument

If I can clearly and distinctly conceive of the essential nature of two things as separate, it must be possible to separate them (God could do it).

I can conceive of the nature of my mind as a thinking, non-extended substance separate from my body.

I can conceive of the nature of my body as an extended, non-thinking substance separate from my mind.

Since I can conceive of these things as distinctly separate it must be

possible

for them to be separate. Meaning they don’t depend on one another, therefore they are two separate substances.

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Critique – Mind Without Body?

Mind

without body is not

conceivable

Is it truly possible to think about a mind without a body? Every frame of reference we have requires senses that use physical data to tell us about the world.

In everyday life we recognise people as being the same as their bodies – our friends and family are flesh and blood bodies, not disembodied souls. Without their bodies we would not recognise them.

It seems impossible then to conceive of the mind without the body, and if this is true then it means that a mind without body is logically impossible.

Premise 2 is flawed.

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Critique – Logically Possible > Reality?

Logical Possibility

does not

dictate reality

Just because we accept the possibility of something does not mean that it is true in this reality.

For example:

I can conceive of a flying horse and imagine how one would work, but just because it is possible in one world does not mean it is true in this world.

There are natural laws that go against this happening.

Logical possibility does not mean physical possibility.

Even if we accept that is possible that the mind could exist without the brain it does not mean it is true in our world/reality.

We should not be using a priori reasoning to make empirical claims about the world and reality around us.

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Critique – Conceivable > Possible?

Descartes invited commentary from the scholars of his day, one Antoine Arnauld raised a criticism that he felt the need to address:The criticism was levelled at Descartes first premise that what is conceivable is always possible. To demonstrate his issue he offered a parallel argument using Pythagoras’ theorem.

Someone ignorant of Pythagoras might well suppose that they could conceive of a right-angled triangle that lacked this property, but it wouldn’t follow that is it actually possible for this triangle to exist. Not even God could create it.

The fact that Descartes can

conceive

of the essence of his mind being separate from his body does not show that it is

actually

possible to separate them.

It is possible Descartes is mistaken, is missing some crucial information or has simply misunderstood the essence of his mind.

This leads on to the famous “masked man fallacy”.

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Critique – Masked Man Fallacy?

I can’t conceive of my father being the masked man.

I can’t conceive of the masked man being my father.

I can conceive of them being

separate people.

The masked-man and my father are therefore two distinct different things.

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Critique – Another Way?

Lois Lane believes that Superman can fly.Lois Lane does not believe that Clark Kent can fly.Therefore Superman and Clark Kent are not the same person.

We cannot automatically assume that subjective knowledge of something (or even a group of things) is enough for making accurate, non-contradictory statements.

What we believe is a property of us, not the thing in question therefore we cannot make accurate statements based purely on our subjective knowledge.

Descartes makes this mistake when he assumes that his “clear and distinct idea” of the body and mind as separate things is enough to show that they must be separate.

His idea is a property of him, not a property of the thing he is considering.

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DIRT

Using a pen of a different colour to the one you originally answered your questions in (just to make sure it stands out in your folder):

Pick one or two questions you did not get full marks on.

Either rewrite them

(in the case of the 3 / 5 mark questions)

or write an extra paragraph that could be added to your

12 mark question

in order to improve it. Make sure you state which questions you are doing.

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Folders – So Far…

Substance Dualism

– The mind is a distinct substance from the body.

Key Terms

Argument from divisibility

Mind is divisible

Body is not divisible

Argument from conceivability

Mind without body is not conceivable.

What is conceivable may not be possible.

What is conceivable tells us nothing about reality (MM fallacy)

Handout

Short Assessment (with DIRT)

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Post-Substance Dualism

As

neuroscience, psychology

and

our understanding of the mind

evolved through the years,

many philosophers began to reject substance dualism due to the reasons we mentioned last lesson.

The development of

evolution

(and the idea that some creatures have more / less complex minds based on their brain structure), seemed to be a death knell for the theory.

Some philosophers therefore embraced

physicalist

theories – the view that minds are entirely physical things, and we’ll be discussing this in the coming weeks.

But in the 90’s a text was written that threw a spanner in the works of physicalism as well

.

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David Chalmers – Easy Vs Hard Problems of Consciousness

Who: David ChalmersWhen: 1966 – PresentText: Facing up to the problem of consciousness.Notes: University professor and influential philosopher. Should probably buy a suit.

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David Chalmers – Easy Vs Hard Problems of Consciousness

Read the section of text you’ve been given. What does Chalmers term the “Easy” problems of consciousness? Why? Give some examples.What is the “Hard” problem of consciousness? Why? Give some examples.Is he correct?

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Recap – Easy Vs Hard Problems of Consciousness

What does Chalmers term the “Easy” problems of consciousness? Why? Give some examples.

What is the “Hard” problem of consciousness? Why? Can you give an example?

What are P-Zombies? Why are they an issue for physicalism?

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Chalmers Easy Vs Hard:

Easy Problem of consciousness:How does the brain integrate, categorize and distribute information?How does it respond to environmental stimuli?How does it focus attention?These things are known as the easy problem of consciousness as they can be functionally defined.That is to say, if we can find the function of the brain that performs these tasks, we have solved the issue.All of these questions are about identifying or specifying mechanisms that perform certain tasks.We’ve not done it yet, but presumably we will do with enough study.

Hard Problem of consciousness:

The

problem of explaining the relationship between physical phenomena, such as brain processes, and

experience.

Experience does not seem to be functionally definable – if we find the mechanisms that perform these functions we would still not know certain key questions:

Why is their performance accompanied by experience?

Why one kind of experience and not another?

Presumably no amount of brain study or

biological understanding

would help us answer these

questions.

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Property Dualism

This led to Chalmers propose a reinvigorated version of dualism – this time based around properties rather than substances.If we start by considering physical properties…

Physical statesPublicFallibleFollow lawsDon’t have qualiaDon’t have intentionality

What if we’ve missed something the obvious?

What if the mental is a property of the physical?

Something new that arises only from the brain and no other physical object?

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Property Dualism

Special set of properties that depend on the physical substance for their existence.

No other physical substance has these properties.

So

consciousness

is a real thing – a real

non-physical phenomenon

, but it cannot exist without the brain to produce it.

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How does it work?

As the brain evolves, it has become more and more complex. Once it has reached a certain level of complexity, mental states

emerge.Mental properties can therefore be said to be emergent – they appear once physical matter has managed to organise itself into a sufficiently complex system.

A way of understanding this idea could be to look at life itself, life only

emerges when matter has reached a certain level of complexity. Too chaotic and life does not emerge.

Alternatively consider a building or a sand castle – the complete structure only

emerges

once the component parts have been formed into a sufficiently complex layout.

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A Special Kind of Property:

It is important to note that the property dualist considers mental properties to be special in that they cannot be reduced to physical properties.This essentially means that (unlike physicalists who believe that all mental states can be explained using the physical) property dualists believe that mental properties cannot be explained simply using physical sciences. Mental properties are not just organisational features of physical matter, they are more.This means that PD’s remain dualists, except this time there are two types of property not substance.

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A Special Kind of Property:

Heat =

Physical property of something and can be reduced to the physical explanation using science.

Happiness =

Mental property of something and cannot be reduced to a physical explanation using science.

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Against Physicalism - Leibniz

"One is obliged to admit that perception and what depends upon it is inexplicable on mechanical principles, that is, by figures and motions. In imagining that there is a machine whose construction would enable it to think, to sense, and to have perception, one could conceive it enlarged while retaining the same proportions, so that one could enter into it, just like into a windmill. Supposing this, one should, when visiting within it, find only parts pushing one another, and never anything by which to explain a perception. Thus it is in the simple substance, and not in the composite or in the machine, that one must look for perception.” – Gottfried Wilhelm Leibniz (1646-1716)

What is Leibniz trying to say here?Do you think he has a point?

Important Note: Essentially Leibniz is pointing out the problem of Qualia here, as such this argument works in support of all kinds of dualism not just property.

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Tasks:

Explain what is meant by property dualism for your notes include:

The relationship between the mind and the body (think of the diagram).Why property dualists consider mental properties to be emergent.What property dualists mean when they say that mental properties are irreducible.

Read pages 242-244 of the textbook:If you STILL don’t have an explanation of qualia – get it down now – Chalmers has a nice outline.What is a philosophical zombie?Why does the possibility of these creatures highlight an issue for physicalism?

When you’ve completed these tasks have a look at the activity on page 243, see if you can figure out whether your partner is a philosophical zombie!

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Philosophical Zombies

Imagine a human with no conscious mental states – lacking in Qualia. Chalmers calls this being a zombie.This zombie perfectly matches a normally functioning person, it is physically identical even down to the brain neurons and it behaves just like everyone else. The only difference is it has no subjective awareness. It does not enjoy any qualia. There is nothing that “it is like” to be this zombie.

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The Philosophy Bit

Chalmers thinks that such a philosophical zombie is conceivable (remember possible world!). There isn’t anything contradictory about the idea. He does however accept that they don’t/can’t exist in this universe (laws of nature).But this is irrelevant, there exists a possible world in which these zombies exist – physically identical to humans except they don’t experience qualia.If this is true then consciousness can’t simply be identical to physical properties.

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Philosophical Zombies

Physicalism claims that consciousness is ultimately physical in nature.

It follows that any world which is physically identical to this one must contain consciousness.

But we can

conceive

of a world which is physically identical to this one, but in which there is no conscious experience – the world of the philosophical zombies.

Therefore physicalism is false.

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Key Points

Property dualists believe that there are two different kinds of thing, they just think the two different things are properties not substances.

Property dualists believe the mental properties to be emergent properties of the physical substance – that is to say, something that emerges when the physical substance has become sufficiently complex.

Property dualists also believe that these mental properties cannot be reduced to the physical – they cannot be explained using physical terms or physical science.

They illustrate this issue with explaining mental phenomena using physical terms in the problem of qualia, Leibniz’s machine and the Philosophical zombies argument

so far…

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Response 1:

A world of P-Zombies is not truly conceivable.

But just try to keep hold of this idea in the midst of your ordinary intercourse with others. Say to yourself, for example: “The children over there are mere automata; all their liveliness is merely automatism.” And you will either find these words becoming quite meaningless; or you will produce in yourself some kind of uncanny feeling, or something of the sort. - Wittgenstein

According to Dan Dennett, whilst there are no explicit contradictions in the argument there are hidden ones.We may fool ourselves into thinking we can strip consciousness away from a persons ability to act, but actually having a mind is integral to performing such tasks.

Can a person really respond intelligibly without Qualia? Without understanding of what they’re saying?

Some

e

xamples:

People responding in a conversation without qualia would mean they don’t understand their own words or yours.

People describing their sense of qualia without actually having it.

I

magining someone experiencing no pain after losing an arm or leg

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Response 1:

A world of P-Zombies is not truly conceivable.

Imagine not experiencing anything? Can you do it? Even if you’re just thinking of a black space you’re still experiencing that thought, that blackness. The life of a P-Zombie simply can’t be imagined. The P-Zombies inner life is non-existant and is therefore unimaginable.We also struggle with imagining meeting a P-Zombie as from our perspective everything about this person is the same as everyone else. So we either are being asked to imagine something that can’t be imagined or something which is very easy to imagine but doesn’t differ from our everyday experience.

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Just because we can conceive of something, that doesn’t mean it is possible. This is because sometimes our conceptions are based on false beliefs.For instance, before the chemical structure of water was discovered, people may have had thoughts such as “I wonder if water is H2O” or “I suspect that water might be H2O, but it might not be”. At this time, people could easily conceive that water was not H2O. But this is not possible, because water just is H2O. So, we might be able to conceive of zombies not being conscious, but if physicalism is true (and we may yet discover that it is, maybe we are missing some crucial information) then zombies would have to be conscious.

Response 2:

What is conceivable is not possible.

A physicalist can summarise this as:Just because we can imagine the existence of these P-Zombies does not mean they can truly exist. Any creature that has the exact physical makeup of a human would also have conscious experience because conscious experience is simply physical. And if they were to lose their minds for some reason, they simply would not behave in the same way we do. They are not possible creatures.

Response:

But if this were true then we would not have an issue with qualia – we would simply be able to study the physical makeup of the creature and be able to deduce it’s mental states.

If mental states are simply physical states then we should be able to access them just by observing the physical (Jacksons Knowledge Argument).

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Response 3:

Possibility tells us nothing about reality:

Just because zombies exist in another world, does not mean they exist in this one. Perhaps we are in one world where mental / conscious states are physical and in the rest they are not.

Our World

Physicalist World

Possible 1Dualist world

Possible 2 P-Zombie World

Response: But this means that the mental is something extra and is extraneous to our needs. If in our world the mind is purely physical then why does it need a mysterious non-physical element for P-Zombies to have consciousness in their world? Surely this is just extra, unneeded stuff?

Physical

Mental

Absent

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Responses:

Which of these criticisms do you think is the strongest? Why?

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Tasks

Make sure you have a summary of the P-Zombie argument down.Why do some people think P-Zombies are not truly conceivable?Why might people believe they are conceivable but not always possible?Why does something being possible not always mean it is reality?

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Dan Dennett’s Final Word

Supposing that by an act of

stipulative

imagination you can remove consciousness whilst leaving all cognitive systems intact… is like supposing that by an act of imagination, you can remove health while leaving all bodily functions and powers intact…

Health isn’t that sort of thing and neither is consciousness.