The challenge from

Neuroscience

‘The brain begins to seem like a magic box, a font of sorcery…how can sending an electric current into a bunch of cells produce conscious experience?

What do electricity and cells have to do with conscious subjectivity? How could a conscious self exist inside such a soggy clump?’

- Colin McGinn, The Mysterious Flame

What’s up

What does Neuroscience tell us about:❄Whether the mind is

simply the brain❄Whether we are free

Is the mind

distinct from the brain?

Phineas Gage❄Survived accident in

which a large iron rod went totally through his head

❄Destroyed much of his left frontal lobe

❄Subsequent personality changes (?)

The Gage puzzle

Personality Brain part

BrainMind

Can science solve the mystery of consciousness?

What’s Pinker’s argument?

“Modern neuroscience has shown that there is no user. ‘The soul’ is, in fact, the information-processing activity of the brain.”

What is Pinker’s argument?

1. Changes to the brain cause changes in the mind

2. If (1) is true, then the mind is reducible to the brain.

3. Therefore, the mind is the brain.

Evidence from Neuroscience

Obvious

Good argument?

1. Changes to the weather cause changes in your lifestyle.

2. If (1) is true, then your lifestyle is reducible to the weather.

3. Therefore, your lifestyle is the weather.

What is Pinker’s argument?

1. Changes to the brain cause changes in the mind

2. If (1) is true, then the mind is reducible to the brain.

3. Therefore, the mind is the brain.

Evidence from Neuroscience

Obvious

Causal link doesn’t entail

identity of linked

entities

What is Pinker’s argument?

1. Everything about the mind can be explained in terms of the brain.

2. If (1) is true, then the mind is reducible to the brain.

3. Therefore, the mind is the brain.

Evidence from

Neuroscience

Simplicity

Compare

Everything about the mind can be explained in terms of the brain.

The mind is affected by the brain

Everything about you can be explained in terms of the weather.

You are affected by the weather.

A puzzle

My Soul

Immaterial substance capable of thinking, feeling, etc

Thinking, feeling, etcPhysical changes to brain

Appearance & reality

What seems to be What is

Memory is a single unified phenomenon

Many different memory systems

that can be disassociated

with one another

Appearance & reality

What seems to be What isMemory is a single unified conscious

experience

Many different, detachable memory

systems at the neural level

Is there really a conflict?

Problem of Consciousnes

s❄Easy problem

❊Correlation between mental states & brain states

❄Hard problem❊How the mind is just the

brain❊Laws explaining

correlation❊Origin of mind

The general argument1. If I have the property P, but

my body lacks the property P, then I am not the same thing as my body.

2. I have the property P, but my body lacks the property P.

3. Therefore, I am not the same thing as my body.

Diversity of Discernibles

Reflection

Conclusion

The Mental & the Physical

No apparent physical properties

Intentionality

Privileged access

Logically possible to exist without the

physical

Length, mass, texture

No apparent intentionality

No privileged access

Logically impossible to exist without the

physical

Relevant readings❄“Can Neurobiology Teach Us

Anything About Consciousness?” (Churchland)

❄“The Puzzle of Conscious Experience” (Chalmers)

❄“The Mysterious Flame” (McGinn)

Libet & the Science of Freedom

2 views of action

Circumstances Agent Intention

Circumstances Agent Intention

“Incline without necessitating”

Argument from Deliberation

The findings of neuroscience and cognitive psychology

General observations of

behavioural patterns

❄Deliberation indicates we have the power to choose

❄Therefore, it is reasonable to think we have the power to choose, unless we have reason to think otherwise

Why are people so predictable?❄Strong correlation between

circumstances & behaviourHume:“Everyone acknowledges that there is much uniformity among the actions of men in all nations and ages, and that human nature remains the same in its forces and operations.”

“If an intimate friend of mine, whom I know to be honest and wealthy, comes into my house where I am surrounded by my servants, I rest assured that he isn’t going to stab me before he leaves, in order to rob me of my silver ink-well; and I no more suspect such behaviour from him than I expect the collapse of the house itself which is new, solidly built, and well founded.”

Laws of behaviour?❄We can understand behaviour by

understanding background/circumstances?

❄Are we subject to psychological laws?

❄If we know all the relevant information, can we be certain of how someone will behave?

Libet’s experimentWithin 30 seconds, wriggle your finger whenever you choose. Don’t plan in advance.

Watch the clock and note when you chose to wriggle your finger.

Findings

Findings❄Steady increase in brain

activity (RP) consistently preceded the time the agents cited as when they experienced the will to move.

❄On average, RP preceded the ‘experience of will’ by some 500 milliseconds.

Libet and others conclude that conscious will is not the initiator of voluntary acting

Instead it is a consequence of an unconscious physical process that triggers the action.

Free will is an illusion"The timing of will, finally, seems to seal the fate of that elusive light bulb. The detailed analytical studies of the timing of action indicate that conscious will does not precede brain events leading to spontaneous voluntary action but rather follows them.” -Daniel Wegner, The Illusion of Conscious Will

The illusion illustrated

My brain gives me the

experience of making my

choice.

My brain determine

s my choice.

My body responds.

My brain responds.

I make a choice.

My body responds

.

Recall: Fact about deliberation❄Deliberate: Sleep or

Exercise?❄You believe:

• that you can sleep or exercise• It is within your control

whether you choose to sleep or exercise It is not. Already determined

by brain :(

Extremely crucial distinctions

Willing to XHaving urge = Will

Will = Experience of will

Experience of willing to X

Having the urge to X

Problem 1❄Will to wriggle finger was exercised

when joining experiment❄“Urge, desire, will, intention”❄Intention to wriggle finger when urge

is detected

In passive state, no actual choice made

Problem 2❄What should we expect to see if our

experience of willing is accurate?❄Consciousness is linked to the brain❄Priming for decision?

❊Break in causal chain may not result in break in brain activity

The empirical findings are inconclusive?

Empirical information needs conceptual processing.

After the empirical, comes the

philosophical

Delgado’s peculiar discoveries

❄ Delgado discovered that stimulating various regions of the brain could cause all sorts of bodily motions ❊ Including frowning, the opening

and closing of the eyes, and movements of the head, arms, legs and fingers…

❄How do you think you would react when your brain is stimulated by a scientist?

Human reactions❄Not only did they act out the movements

without surprise or fear, but they also produced reasons for them.

❄Example:❊Electrical stimulation of the brain produced

“head turning and slow displacement of the body to either side with a well-oriented and apparently normal sequence, as if the patient were looking for something.”

❊Repeated six times over two days, with similar outcomes

Human reactions❄The subject, who did not know

about the stimulation, considered the activity spontaneous and offered reasons for it.

❄When asked “What are you doing?” he would reply, “I am looking for my slippers,” “I heard a noise,” “I am restless,” or “I was looking under the bed.”

Analysis of Reasoning❄Evidence for freedom based on

experience❄But manipulation could produce the

same experience(1)Same experience indeed?(2) Even so, what does this prove?

Evidence for main claim❄Subject experience movement as

voluntary although it was due to brain stimulation❊Consistent correlation❊Not surprised at movement❊Offered reasons for movement

Same experience?❄Not voluntary

❊But participants tend to rationalise actions to make sense of movement

❊Confused reflex action with voluntary action

❄Actually voluntary❊Brain stimulation lead to strong desire

which subject acted on❊Evidence not conclusive

Analysis of Reasoning❄Evidence for freedom based on

experience❄But manipulation could produce the

same experience(1)Same experience indeed?(2) Even so, what does this prove?

Even so, what does this prove?

❄Sensation of will can be produced, but need not always be this way?❊E.g. brain stimulation can cause us to

have perception of objects❊Doesn’t prove all perceptions are

inaccurate❊Rational to take perception as accurate

unless we have reason to think otherwise?