Archive for ‘perception’

October 1, 2017

Color blindness

by Neil Rickert

I am color blind.

Well, not really.  My color vision is fine, thank you.  However, my color vision is abnormal.  That doesn’t mean that it is bad.  It just means that it is different from what is typical.

I should note that I am posting this because I intend referring to it in a future post about human cognition and perception.

Growing up

As a child, I had no idea that there was anything unusual about my color vision.  The world looked the way that people described it, as best I could tell.  I developed an interest in electronics, and I never had any difficulty with the color coding of resistors and other components (giving the resistance as a series of color bands).  As far as I could tell, my vision was normal.

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May 27, 2015

Searle on direct realism

by Neil Rickert

As I hinted in my previous post, I want to discuss some aspects of Searle’s theory of perception.

Searle makes a good start with:

I believe the worst mistake of all is the cluster of views known as Dualism, Materialism, Monism, Functionalism, Behaviorism, Idealism, the Identity Theory, etc. The idea these theories all have in common is that there is some special problem about the relation of the mind to the body, consciousness to the brain, and in their fixation on the illusion that there is a problem, philosophers have fastened onto different solutions to the problem. (page 10).

I agree that those are mostly mistakes.  Searle continues with:

A mistake of nearly as great a magnitude overwhelmed our tradition in the seventeenth century and after, and it is the mistake of supposing that we never directly perceive objects and states of affairs in the world, but directly perceive only our subjective experiences.

That is Searle’s statement about his direct realism.  I do support the view that perception is direct, but I avoid the term “direct realism” because the word “realism” seems to carry some unnecessary metaphysical baggage.

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August 12, 2014

Constrained invention

by Neil Rickert

This will mostly be a copy of what I recently posted in a Yahoo groups discussion.  And, incidentally, Yahoo badly mangled that post (stripped out most of the formatting).

As background, I’ll note that in an earlier Yahoo groups post, I had indicated that I was opposed to the view that perception is passive.  This seemed to puzzle some participants in the discussion.  So my post — the one I am quoting — was intended to explain what I mean when I say that perception is active.

The quoted post

You guys need to get out more. You are trapped in a world of logic, and unable to think outside that box.

You both seem committed to God’s eye view thinking, though you may be in denial over that. So you see perception as a system to report to you what is seen by the hypothetical God. But how could that ever work?

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March 28, 2014

Direct vs. representational perception — the discussion

by Neil Rickert

In prior posts (here and here), I have illustrated representational methods and direct methods.  The illustrations were from science, because that is more public so easier to demonstrate the contrast.  I believe that they illustrate well enough, the distinction between direct and indirect perception.  Both aim to provide the same sort of information about the world.  The method is different, though perhaps the differences are small enough to be confusing.

The primary distinction here is that direct perception is simpler and more direct, and does not rely on computation or inference.  This is why I see direct perception as more likely to be what has evolved, and thus a more likely candidate for explaining human perception.

Double categorization

One way of seeing the distinction is to look at it in terms of categorization.  Here, I use “categorization” to refer to the dividing up of the world into parts (or categories).  This comes from the old idea (from Plato?) of carving the world at its seams, though the seams might actually be man-made.

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March 28, 2014

Direct measurement of temperature

by Neil Rickert

In an earlier post, I described the representation measurement of temperature.  In this post, I describe the direct method.  The contrast is intended to illustrate the distinction between representational theories of perception and direct theories of perception.  By using an example from science (or perception written big), we illustrate in a way that is easier to see.

The design of the instrument

The design is almost the same as described in the earlier post.  There is one addition.  The mercury column in the capillary tube is directly calibrated in temperature.  That is to say, there are graduation markings on the thermometer, from which we can directly read off the temperature.

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March 27, 2014

Representational measurement of temperature

by Neil Rickert

As indicated in the previous post, I plan to use the measurement of temperature to illustrate some ideas about perception.  This post will give a representationalist account of measurement, as an illustration of indirect perception.

The apparatus to be used is very similar to a mercury thermometer.  I shall assume that the reader is reasonably familiar with traditional analog thermometers, and how they are used.

The design of the instrument

The thermometer uses a glass tube.  At the bottom of the tube, there is a largish bulb which can be filled with mercury.  Above the bulb, the glass tube contains only a very narrow tube of small diameter, sometimes called a capillary.

The bulb is initially filled with mercury, and the mercury extends to part way up the capillary tube.  Above the mercury, the tube is empty.  The air is pumped out, though it need not be a perfect vacuum.

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March 27, 2014

Contrasting direct and representationalist (indirect) perception

by Neil Rickert

In a discussion at another site, I am noticing some misunderstanding of what is meant by direct perception.  I’m seeing comments similar to “vision uses photons, so is indirect.”  Those who favor direct perception have never denied that vision uses photons, retinal receptors and neurons.  The usually prefer saying that visual perception is mediated by photons, neurons, etc.  What they disagree with, is the idea that first a representation is formed inside the head, and then we perceive that representation.

Apparently this distinction is confusing.  So I plan a short series of posts where I contrast direct perception and representationalist perception.  This post is the introduction to that series.  The subsequent posts in this series are:

Illustrating with science

It is sometimes said that scientific discovery is learning written big, and scientific data acquisition is perception written big.  The problems that science must solve to acquire useful data are similar to the problems that a perceptual system must solve to gather information about the world.  I shall use that analogy between perception and science, to illustrate what is meant by direct perception.

My next post in this series will give a representationalist account of getting temperature data.  I’ll follow that with a post on a direct way of getting temperature data.  And then, in one more post, I will attempt to point out the important distinctions.

 

January 8, 2013

Perception – categorization

by Neil Rickert

I have mentioned categorization in earlier posts, suggesting that it is important.  The trouble with the words “category” and “categorization” is that people use them in different and conflicting ways.  And that is perhaps why the importance of categorization is not well appreciated.

Ian, over at his “Irreducible Complexity” blog, has just posted something about categories that illustrates the different ways that categorization is used.

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January 4, 2013

Connecting science with perception

by Neil Rickert

I have two ongoing series of posts, one on perception and the other on how science works.  These are very much connected, as I will explain in this post.

My interest in the main topics of this blog led me to study the question of how humans learn.  I understood, all along, that the increase in scientific knowledge is closely related to learning.  Or, as I think Quine puts it, science is learning writ large.  Thus I used the growth of scientific knowledge as a publicly observable instance of learning.

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January 3, 2013

Perception – discrimination

by Neil Rickert

Perceptual discrimination is the act of distinguishing between different items that are in the perceptual field.  In this post, part of my series on perception, I will look at barcode scanning to illustrate what discrimination is, and its role.  And I will use this example to further clarify the distinction between direct perception and indirect perception, at least as I use those terms.

These days, we see bar codes on many of the items that we purchase.  And the store clerk typically uses a scanner to read that bar code and identify which item we are purchasing.

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