silencing the experience of changefolk.uio.no/sebaswat/materials/watzl_silencing_columbia...show...

Silencing the Experience of Change Sebastian Watzl (Harvard University)

1

Our focus today:

Visual experiences as of change.

Change of Color

Change of Size

Change of Shape

Change of Location (Movement)

A further fact?

Change of

Color

Change of

Shape

Change of

Size

Change of

Location

Experiences as of ...

Color Shape Size

...

Location

Maybe not ...

Temporal properties are special:

experience not only represents them

it also has them

time

Your stream of experiences of color

Temporal properties are special:

experience not only represents them

it also has them

time


actual time (in your head)!

represented color (not in your head)!


fixes

Your experience of change of color

time

time

= =

The Structural Matching Thesis

There is a close match between the temporal structure of the content of experience and the temporal structure of experience itself

Applications to the experience of change:

You experience a change from red to blue just in case you first experience red and the blue

You experience faster (slower) changes in quality Q just in case your stream of Q experiences is faster (slower)

Attractions: No-further-fact-intuition

Would allow “reading-off” the changes your experience presents to you from your stream of experience of the properties that are experienced as changing.

Simplicity

Explains something complex (experience as of change) in terms of something simple and uncontroversial (experience as of non-temporal properties).

Cinematic Thinking (Time-is-special thinking)

Experience represents temporal properties by its own temporal properties (snapshots or unified temporal wholes)

The Structural Matching Thesis

My Goal

Show that a newly discovered visual illusion directly challenges the structural matching thesis.

The experience of change is a further fact: experiencing a certain quality as changing (at a certain rate) is a separable and phenomenally manifest dimension of visual experience.

The experience of change thus is not that special, after all.

The Illusion*

*Suchow and Alvarez (2011): Motion silences awareness of visual change. Current Biology

Stationary Condition Change of Color Rotation Condition

The Illusion*


Change of Color

The Illusion*


Change of Size

The Illusion*


Change of Shape

The Illusion*


Focus on a particular dot

#53

Against Structural Matching


Stationary Condition

Rotation Condition

time



Stream of Actual Colors

time

time time

= ≠


Different temporal content

You experience fast changes of color in the stationary condition, while you experience much slower changes of color in the rotation condition, i.e. you experience a very different rate of change of color in the two conditions.

Same temporal layout

At each time t during the rotation condition just like during the stationary condition, you experience the dots as roughly having the colors they have at t, i.e. your color experience of color is changing at roughly the same rate in the two conditions.


So, there is no close match between temporal content and temporal layout of the experience

So, the structural matching thesis is false.

Alternative Explanations?

Maybe motion does not silence the experience of change but freezes the experience of color/shape/etc.?

Alternative Explanations? 1. Freezing?


Rotation Condition

time



Stream of Actual Colors

time

time

≠

time

≠


An experimental test: The Flip Experiment

Rotation Condition

time

Your stream of experiences

of color Stream of

Actual Colors

time time


of color

Freezing Proposal Silencing Proposal



Rotation Condition

time


of color Stream of

Actual Colors

time


of color

Freezing Proposal Silencing Proposal

time

subjects do not notice this flip!

Flip color back to original color subjects do

notice this flip!



Rotation Condition

time


of color Stream of

Actual Colors

time


of color

Freezing Proposal Silencing Proposal “Flip” color to “close” color

time

subjects do not notice this flip!

subjects do notice this flip!


time

from Suchow and Alvarez (2011): Motion silences awareness of visual change. Current Biology


On the basis of The Flip Experiment, the freezing proposal should be rejected.


Maybe color information is updated in the rotation condition less frequently?

So, the rate at which your experience is changing is slower in the rotation condition

Alternative Explanations? 2. Infrequent Updating?

red yellow green blue red


Rotation Condition

Changes quickly

Changes less quickly

Rests on a confusion betw. smoothness and cycle time.

Cycle time is the same (see flip experiment).

Cycle time is needed for structural matching.

Alternative Explanations? 2. Infrequent Updating?

red yellow green blue red


Rotation Condition

Changes smoothly

Changes less smoothly

SAME CYCLE TIME!!

One obvious difference between the stationary condition and the rotation condition: in one the dots are moving!

Experience of change requires binding across time (now it is this way, now the same thing is a different way). If the object moves to fast, you can’t keep track of any single object across time, binding is prevented, and so you don’t experience change

Compatible with best way to understand the structural matching thesis.

Alternative Explanations? 3. Tracking Failure?

Unclear how it explains that there is a difference in your experience of changes in the collective of dots as a whole.

Bigger Problem: silencing occurs even when no dot is moving (“The background rotation condition”

Alternative Explanations? 3. Tracking Failure?

a. Radical Indeterminacy

During TS you do not experience # 53 as having any specific hue at all (i.e. indeterminate between all hues on the color wheel)

Problems:

how would something with experienced as having a completely indeterminate hue look like?

would have to be correct for all dots: But then all dots would look to be the same hue! But they don’t!

Alternative Explanations? 4. Color Indeterminacy?

b. Mild Indeterminacy

During TR you experience # 53 as having a more indeterminate hue h (e.g. h could be indeterminate between red and orange) than during TS.

Problem:

Is the experienced h constant in the rotation condition?


Dilemma:

Assume that # 53 is experienced as having a constant h, e.g. (generic, indeterminate) red. Incompatible with the results of The Flip Experiment

red red red red red red red red


Dilemma:

Assume that # is experienced as having a non-constant h

Now like infrequent updating


During TS you do not experience each dot individually, but only the dots collectively.

Problem:

Might be true, but doesn’t explain the difference in temporal phenomenology (measured by the silencing factor) during the two phases: During TS the dots appear to change fast.

During TR the dots appear to change slower.

Alternative Explanations? 5. Sortal Indeterminacy?

The Standstill case can be seen as a form of change blindness: a change is happening in front of your eyes, but you fail to see it.

Fred Dretske* has recently proposed that other forms of change blindness are cognitive, and not perceptual failures: not failure of seeing a change (since temporal atomism is

true you can’t specifically be blind to changes). But failure to see that there is a difference between how

something is at one time and how it is at a different time.

Can this idea be applied here?

*Dretske, F. I. (2004). Change blindness. Philosophical Studies, 120, 1-18

Alternative Explanations? 6. Comparison and Judgment?

No, the “seeing-that” proposal cannot be applied here (Dretske, I believe, would agree!):

Can’t explain appearance of slowing down.

Changes are not concealed, but phenomenally manifest (phenomenally present during TS, and phenomenally absent/slowed down during TR).

Would mistakently say that during TR you do experience fast changes, while you report/believe that there are slow changes. This is phenomenally inadequate.

Alternative Explanations? 6. Comparison and Judgment?

Therefore ... (after all)

The Structural Matching Thesis should be rejected.

Extending Cinematic Atomism? 1 s

Extending Cinematic Atomism? 1. Non-cinematic atomism

s In The Illusion the experience of motion silences the

experience of chance.

Non-Cinematic atomism about the experience of change can explain that, and captures what was essential to the atomistic idea!

Non-cinematic atomism

Experiences as of temporal properties supervene on the temporal order and duration of experiences as of non-temporal properties.


s

time

time

Stationary Phase

Rotation Phase

Total stream of experiences Your experience of change of color

Your experience of change of location

≠ ≠ ≠

Non-cinematic atomism is unmotivated:

1. Must give no-further-fact intuition, simplicity and obviousness.

Can’t in any obvious way “read-off” the experience of temporal properties from the experience of non-temporal properties.

Given the temporal order and duration of your experience as of non-temporal properties, it remains an empirical question which temporal properties/changes you experience. In this sense, the experience of change is a clear further fact!


s

2. Must give up cinematic motivation.

“[E]xperience presents temporal phenomena in virtue of its own temporal layout […] [where there is a] direct link between the temporal properties of perception, and its temporal content […]”*

Experience would not “present temporal phenomenal in virtue of its own temporal layout.” The temporal contents of experience do not even crucially depend on the temporal properties of the experience itself.

*Lee, G. (2007). Consciousness in a space-time world. Philosophical Perspectives, 21 (1), 341-374


s

3. Must give up naive realist motivation.

“the world induces experience’s temporal structure (at least in the good case).”*

“Object-time” (here: the rate at which the dots are represented as changing) and “act-time” (here: the rate at which your experience is changing) can come apart:

Your experience of hue in both phases changes in the same way, while the changes that your experience presents to you in both phases differ.

*Philips, I. (2009). Experience and time. Ph.D. Thesis (University College London)


s

Non-cinematic atomism does not vindicate the “non-further fact” idea and as such is unmotivated.


s

Extending Cinematic Atomism? 2. Holistic Unificationism (Dainton?*)

s

*Dainton, B. (2008). Sensing change. Philosophical Issues, 18(1), 362-384

time

Total stream of experiences

Diachronic unity relation

+

fixes Experiences of change (in location, color, size, shape, ..)


s The silencing results imply the (empirical) possibility of

a fragmentation of time consciousness:

You do experience (fast) changes of location

You do not experience (fast) changes of color/size/shape)


So, experiences as of change do not supervene on:



s

Diachronic unity relation

time


+

By the same argument, experiences as of change do not supervene on: total streams of experience + retentions of earlier total experiences

Retention of earlier total experience

* discussed in: Dainton, B. Temporal consciousness, The Stanford Encyclopedia of Philosophy

Extending Cinematic Atomism? 3. Holistic Retentionism (Husserl?*)

s

time


+

Accounts that can capture this insight:

Specious Present View

Holistic Retentionism

Holistic Temporal Atomism

They all agree that (in an important sense) the experience of change is ...

A further fact!!

Change of

Color

Change of

Shape

Change of

Size

Change of

Location

Experiences as of ...

Color Shape Size

...

Location

Change is a separable and phenomenally manifest dimension of visual experience

One Further Implication: Change Blindness

Since the silencing illusion depends on the absence of focal attention, my result suggests that outside attention the experience of change is selectively impoverished.

Change-blindness, thus, generally may just be what the term suggest: a selective blindness to change. It provides no support to the view that our visual experience of non-temporal properties is poor (or absent) outside the focus of attention (as suggested by Tye (2010)*).

*Tye, M. (2010). Attention, seeing, and change blindness. Philosophical Issues, 20 (1), 410-437

The END

Thanks especially to: Jordan Suchow for the beautiful experiments, very insightful comments, and general help.

Thanks also to: George Alvarez, Susanna Siegel, Enrico Grube, Sean Kelly, Farid Masrour, John Morrison, and an anonymous referee, for very helpful comments and discussion.

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