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Transcript
MIND LECTURES 2
Searle on Consciousness
Four Mistaken Assumptions about the Mind –
Body Problem
The distinction between mental and physical cannot be challenged.
Is it true that the mental and physical are opposite categories?
1.
The notion of reduction.
Are all reductions of the same kind?
1.
Causation and Events.
Are all causal events asymmetric in time.
1.
The transparency of identity.
Can we really discover that a mental event is identical to neurophysiological event?
1.
Searle’s Biological Naturalism 1

Conscious states, with their subjective, first-person ontology, are
real phenomena in the real world. We cannot provide an
eliminative reduction of consciousness, showing that it is just an
illusion. Nor can we ontologically reduce consciousness to its
neurobiological basis, because such a third-person reduction
would leave out the first-person ontology of consciousness.
Searle’s Biological Naturalism 2


Conscious states are entirely caused by lower level
neurobiological processes in the brain. Conscious states are
thus causally reducible to neurobiological processes. Causally
speaking they are not something over and above
neurobiological processes.
Supervenience is irrelevant. There are two kinds constitutive
and causal. Constitutive is not relevant to consciousness and
neurobiology. Only causal is.
Searle’s Biological Naturalism 3

Conscious states are realized in the brain as features of the
brain system, and thus exist at a level higher than that of
neurons and synapses. Individual neurons are not conscious, but
portions of the brain system composed of neurons are
conscious.
Searle’s Biological Naturalism 4

Because conscious states are real features of the real world,
they function causally. My conscious thirst causes me to drink
water.
The distinction between the mental and the physical



Physical systems do not have to exclude the possibility of
having states which are qualitative and subjective.
Nothing in an expanded notion of ‘physical’ makes it the case
that subjective qualitative states are non-physical.
Mental states might not be extended in space, but they are
nevertheless located in space and episodic over time.
Reduction Reexamined





Causal reduction: A is causally reducible to B only if A has no
causal powers over and above the causal powers of B.
Ontological reduction: A is ontologically reducible to B only if
x’s being an A is just the same as x’s being a B, A = B.
A is causally reducible to B
does not imply that
A is ontologically reducible to B.
Simultaneous causation

Some causal events are asymmetric and in time:


Billiard Ball A strikes Billiard Ball B and causes B to move. Event X: A
striking B caused event Y: B’s moving, to occur. The causal sequence
is temporally ordered in the sense that the cause is prior in time to
the effect.
Some causal events are not asymmetric and ordered in time:

Gravity causes a table to stay located on the floor. However, the
force of gravity simultaneously and continuously exerts this force
while the table stays on the floor as an effect of the force.
Searle against Materialism and Dualism


Materialism is the view that the physical world is sufficient for everything
that there is. However, it is false since it leaves out subjective qualitative
features of human experience. It leaves out the ontology of subjective
states.
Dualism is problematic since:
1.
No one has succeeded in giving an account of how the two realms interact.
2.
The postulation of two realms is unnecessary. One can account for both first-person
facts and third-person facts without two realms.
3.
The postulation creates problems, such as the problem of mental causation.
Searle on the structure of consciousness:
Qualitative character


Qualitative character = the what it is like feature of
consciousness.
Many philosophers maintain that only some conscious states
have a qualitative character. For example, being in pain does
have a qualitative character, but believing that it is going to
rain does not have a qualitative character.
Searle on the structure of consciousness:
Subjectivity

Conscious states are subjective in that they only exists as experienced by a
subject, typically human.

Ontological subjectivity means the state has a first-person ontology.

Epistemic objectivity vs. subjectivity:


‘Jones is six feet tall’ – independent of the feelings and attitudes of anyone –
epistemically objective

‘Jones is nicer than Tom’ – dependent on the feelings and attitudes of individuals –
epistemically subjective
Ontological subjectivity does not imply Epistemic subjectivity.
Searle on the structure of consciousness:
Unity



Conscious experience is unified in that our conscious experience is in a
unified field. We do not experience things as separate and disjoint or as
divided between two conscious fields.
Conscious experience as unified is a feature of normal functioning brains. It
is not a claim about abnormal or degenerate cases of experience.
A central question in the philosophy of mind is what explains the unity of
conscious experience. In virtue of what is our conscious field bound together
as a unity? How do different stimuli bind together to form a unified field?
Searle on the structure of consciousness:
Intentionality



Intentionality is the feature of experience whereby the experience is about
something.
Intentionality is the aboutness or directedness component of experience.
Seeing a red chair is having a perceptual experience of a red chair, the
experience is directed at and about a red chair. And the content of the
experience can be communicated by a proposition: I see a red chair.
Searle on the structure of consciousness:
Mood



Conscious experience has a flavor or a tone. One finds oneself
in various moods.
Moods ≠ Emotions, since emotions are necessarily intentional
and moods are not necessarily intentional.
Moods can predispose us to emotions.
Searle on the structure of consciousness:
Center and Periphery



A conscious field is susceptible to a distinction between the
center and the periphery.
Some phenomenon are at the center of my attention. And
others are at the periphery, but are such that they can be
brought to the center.
One’s attention brings things into the center and out of the
periphery.
Searle on the structure of consciousness:
Pleasure & Unpleasure



Conscious experience always comes along with some pleasure
or unpleasure.
Conscious states can be evaluated along a spectrum of
pleasure and non-pleasure.
Question: are any conscious states purely neutral?
Searle on the structure of consciousness:
Situatedness



Conscious experience always comes against the background of
a situation, which may not be one’s point of focus, but which
informs and structures their conscious experience.
The situatedness and background is not part of the center of
focus.
Certain facts that structure the background can be brought to
the center of attention.
Searle on the structure of consciousness:
Active and Passive Consciousness




Some conscious experience involves the experience of volition
or agency.
Some conscious experience involves the experience of passivity
and non-agency.
The distinction is not sharp, but there are clear cases of active
and passive aspects of conscious experience.
Perception has active components, but is experienced,
generally, as passive.
Searle on the structure of consciousness:
Gestalt Structure: I
Searle on the structure of consciousness:
Gestalt Structure: II
Searle on the structure of consciousness:
Gestalt Structure: II

Our experience is organized.

It can be organized in different ways.


Sometimes in our experience we fill in details to make
something that looks like one thing appear more like something
else.
There is a figure – ground structure to our conscious
experience.
Searle on the structure of consciousness:
Sense of Self

Conscious experience comes along with a sense of self.

A sense of who one is.

Conscious experience presupposes a subject.

Question: what is the nature of the self that is the subject of
conscious experience. Does consciousness presuppose a
substantial self that is numerically identical over time.
Two views on consciousness:
Mysterianism


Contingent mysterianism: explaining consciousness in terms of
current resources is a mystery. We don’t have a good
understanding of how physical states can cause physical
subjective qualitative states, or how mental states that are nonphysical could cause physical states.
Necessary mysterianism: consciousness cannot be explained
because of a fundamental explanatory gap between the
physical and the phenomenal that cannot be crossed because
of the structure of our concepts.
Two views on consciousness:
Panpsychism



Panpsychism is the view that everything at the fundamental
level is conscious, and thus there is no problem of how
consciousness comes out of the fundamental level of reality.
Problem: Even if everything at the fundamental level is
conscious, we still have a further question – How do little bits of
consciousness compose together to form conscious experience?
Are there any laws that govern when a composition of
conscious parts constitutes a composite of consciousness?
Two Approaches to Studying Consciousness: Building
Block Approach

Building Block Approach: find out the neural correlates of individual
conscious experiences, such as perception or taste. Avoid looking at
the whole conscious field. Instead study degenerate cases.
Blindsight: Damage to visual area 1, they are blind in a certain area
of the visual field, but they can act in response to the blindness with
action that is appropriate. Such as grasping at what is absent in the
damaged area of the visual field.
Binocular Rivalry: Right eye vertical lines, Left eye horizontal lines. No
grid at conscious level, instead switching back and forth. Locate the
point where the switching occurs.
Two Approaches to Studying Consciousness: Unified
Filed Theory Approach

Unified Field Approach: The whole field of consciousness is the area
of investigation, not a simple quale of redness in the field.
Subjectivity in the whole field is what is relevant.
Main distinction:
Don’t ask: How does the brain produce a simple quality of perception,
such as a red quale, which is a building block of consciousness?
Instead ask: How does the brain produce the whole unified field of
subjective consciousness?