Direct perception: Ecological realism and perception-action - philosophical foundations.
An invited philosophy department seminar given by Dr. PJ Treffner in
New Zealand. Questions follow.
Time tags below.
Almost all current theories of perception are a variant of the same theory - indirect perception: Supposedly, WE CAN NOT
KNOW our world directly; all we can "know" directly are physical, meaningless, sensations at our body's sensory surfaces - and then INFER a meaningful, external world - all "represented" INSIDE our brain. Our awareness of "the world" is therefore one step removed from reality. Thus, it is said we do not perceive the chair itself (a stance pejoratively called "naive realism"); we (our brains) only access a physical "retinal image" and INFER the chair exists!
We can know nothing with certainty! We only indirectly know the world, they say.
Opposing this nonsense are an increasing group of serious, competent scientists from the tradition known as ECOLOGICAL PSYCHOLOGY. They promote a self-consistent theory based on modern scientific and empirical evidence, especially evolutionary theory and dynamical systems (complexity) theory. Philosophically, this approach argues for
DIRECT PERCEPTION theory - that we CAN know our environments and apprehend the meaning of it DIRECTLY, without the assumption of internal mediation and a "neural representation".
Brains are important, sure, but not sufficient.
Direct perception theory emphasises the need for (external) INFORMATION in the analysis. This was originator
James Gibson's main
point: perception is not based on sensations; it is based on information.
Perception is not about images
...it is about action and the awareness of AFFORDANCES - based on the detection of INFORMATION, not on the creation of internal models. This is exciting but difficult
21st Century science, not the simplistic
20th Century version of
Cartesian dualism, and its variants. However, a few modern philosophers (
Searle - 1:01:08) are admitting that
Gibson is correct...
00:55 -
VIDEO - instability of perception
02:04 - cause of all the confusion -
Descartes
04:36 - the nonsense of sensation-then-perception
07:38 - the assumed theory of perception
09:49 - the "argument" from illusion
12:19 - VIDEO - spinning ballet illusion
13:11 - illusions and importance of context
14:21 - illusions, retinal images, size constancy
15:08 - Gibson and texture gradient
17:19 - eye height information - (self) perception/size perception
19:01 - phenomenology...behaviourism...functionalism
21:12 - type-type vs. token-token identity theory
24:28 - problems of functionalism - "easy/hard problem"
30:40 - action and affordances - stair climbing
30:50 - VIDEO - climbing goats
31:07 -
Warren's experiments on stair climbing
32:01 - maximum height perceivable? - results - scaling
33:29 - preferred height?
33:43 - preferred height: results - minimum energy
34:14 - preferred height perceivable?
34:28 - preferred height perceivable: results
35:01 - monument steps (and fail)
35:20 - affordances (Gibson): direct perception
37:54 - walking through doorways (Len
Mark's research)
38:00 - walking through doorways: results
38:29 - passable doorway perceivable?
39:40 - other animals? (VIDEO during QT-Question Time)
41:33 - summary: Gibson's affordances and information
42:21 - information is detected; affordances are perceived
44:34 - VIDEO - motion information - occlusion
47:09 - VIDEO - now you see me now you don't!
47:23 - VIDEO - occlusion & point light displays
47:46 - summary - occlusion
48:58 - development and learning - kitten carousel
49:44 - EJ Gibson's visual cliff
50:58 - driving, optic flow, Gibson's field of safe travel
51:52 - VIDEO - optic flow (also during QT)
52:18 - VIDEO - our locomotion experiments
52:28 - moving room and vision for balance
52:44 - VIDEO - moving room (
David Lee) (also during QT)
53:51 - VIDEO - artificial intelligence and affordances?
54:21 - indirect versus direct perception
55:07 - perception-action cycle
55:28 - driving inattention (phones) - our research
56:04 - the "hard problem"?-subjective consciousness??
59:32 - the answer!
1:01:08 - VIDEO - Searle - Gibson: "I think he's on the right track"
1:03:05 - VIDEO - Searle - action fundamental for perception
--------
Question Time (with videos) --------
1:04:21 - Q. Misperception? VIDEO: optic flow
1:07:30 - VIDEO - optic flow driving (David Lee)
1:09:19 - VIDEO - moving room (full)
1:10:04 - Q.
Innate perception vs. learning?
1:11:28 - VIDEO - climbing goats (full)
1:13:32 - VIDEO -
Big Dog robot (full)
1:14:32 - Q.
Does affordance change or perceiver change?
1:15:18 - VIDEO - animals' affordances - kea parrot
1:18:38 - Q.
Virtual world affordances and "metaffordances"?
1:29:55 - Q. Was the (potential) affordance there before I existed?
PDF:
http://metaffordance.com/papers/JackTreffner-DirectPerception-Sept2012
.pdf
Technology's "metaffordances":
https://www.youtube.com/watch?v=-NpMxKdImKw
http://www.metaffordance.com
- published: 26 Mar 2014
- views: 1593