American Perception Of Reality

[AisA]

David.

1) I agree that perception and inference are two different things.

2) My use of the term "directly" was only meant to add emphasis, not to imply that there is such a thing as "indirect perception".

3) When you say that you see no need to defend the validity of sensation, that we only need to uphold the validity of perception, what do you say to those who declare that our sense organs only give us "indirect", "distorted", "filtered" and "subjective" contact with reality? Objectivism has two defenses to this line of attack, but both involve a direct defense of the senses. How would you defend the validity of perception without answering this attack on the senses?

4) You said: "If perception did only tell us "an existent exists", and nothing more, then we could never tell identify anything -- we'd just have a stream of useless information "Something's there; something's there; something's there". Perception has to include some information about what it is (basically, all information that we need to make an identification)"

I certainly didn't mean to imply that perception never tells us anything except that "an existent exists"; poor choice of words on my part. I didn't elaborate on the process of forming a concept, which comprises perceiving an entity's characteristics, such as its shape, color, size, weight, location, mobility, etc. and then, on the basis of such accumulated perceptual information, perceiving that one entity is sufficiently similar to other entities, and sufficiently different from all others, to consider them as units to be integrated into a concept. I didn't go into that because I assumed we had the same understanding of the role of perception in concept formation and I thought you were asking about the automatic processes that make previously conceptualized information available to us after a concept is formed.

My point was that after we have learned the concept "apple", we do not have to repeat this process of observing similarities and differences, integration into a concept, etc, each and every time we perceive an apple. The knowledge that the entity in front of us is an apple is available to us automatically via subconscious recall -- and that happens whenever you choose to focus on the apple and think about it. Do you have a different understanding of this process?

[DavidOdden]

3) When you say that you see no need to defend the validity of sensation, that we only need to uphold the validity of perception, what do you say to those who declare that our sense organs only give us "indirect", "distorted", "filtered" and "subjective" contact with reality?

Primarily I would argue that that position doesn't mean anything or make sense. It's important to not deny the "informational limits" on our sense organs, for example humans cannot directly see ultraviolet light or electrons, i.e. they are not perfect sensors of the nature of reality with infinite resolution. The charge of "indirectness" would only mean something if there were something "more direct", for example if the apple directly entered our brain, bypassing the eye and the optic nerve. The representationalists / indirect realists seem to actually believe that there are tiny images of apples broadcast into the brain and the brain "sees" these internal images (possible via a miniature robot with a vue-screen and a bunch of levers). That would be an example of indirect perception; once you make concrete what indirect perception would be, in the context of modern knowledge it's not a serious contender.

Distortion is a hard concept to get a grip on. Obviously the sense-organs don't present the mind with a perfectly faithful and detailed representation of reality. But the relationship is law-like, not random. To give a concrete example, physical sound waves are audible only if they have a certain minimum sound pressure level, where greater sound pressure levels are needed to hear a lower frequency than a higher frequency, until about 2Khz where it reverses. That kind of "distortion" is no threat to the claim that perception is valid -- it obeys a law, which we know (reasonably well -- there is considerable personal variation because we all have different ears). The nature of the sound can easily be verified by mechanical devices where we can be even more specific about the laws that relate the input sound to the measurement, so that we can be specific about the nature of so-called distortions via unaided sense organs.

My point was that after we have learned the concept "apple", we do not have to repeat this process of observing similarities and differences, integration into a concept, etc, each and every time we perceive an apple.

Absolutely. No question.

The knowledge that the entity in front of us is an apple is available to us automatically via subconscious recall -- and that happens whenever you choose to focus on the apple and think about it. Do you have a different understanding of this process?

The question is what constitutes "automatic" and "subconscious"; this is relevant in dealing with what could be considered "marginal" cases, i.e. identification either of something unfamiliar or of something familiar under strange conditions. I think focus is probably the essential consideration. My favorite involves the McGurk effect, and the experiment involves showing a tape of a mouth (fairly large screen) saying "ba, va, za, da" etc, and you get to hear the sounds -- but the mouth saying "ba" might have the sound "da" coming out. Ordinarily, people report hearing what the face does and not what the ear hears (within certain limits). When the subjects learn the trick, they focus harder on the auditory channel and disregard the visual, so people then are better at correct identifications. So IMO, the perceptual illusion experiments don't really tell us about perception per se, they tell us about under-focused perception.

So I would say that the automaticity and subconsiousness of identification is related to the percepts that you have available to you, and it may not be possible to make a correct automatic identification.