Ayn Rand Explained

Recommended Posts

Contrast by proximity, I'd call it- taken advantage of in photography (specially monochrome)

to accentuate aspects of the image.

(When you all pull the cameras out this Xmas to shoot the family, remember: watch the background!)

Share this post

Link to post
Share on other sites

My, how topics drift. Anyway, this explains the checkerboard illusion. Also, grab a piece of paper, cover the image with the paper so you can see only squares A and B through two holes in the paper. Squares A and B will look alike.

That proves that the squares are the same shades of grey. I'm not sure at all that the explanation fully explains the -change- in perception. The first time we see that, we see them as different shades of grey. (In fact, some folks are so sure of what they 'see with their own eyes' that they actually get angry at claims that the squares are the same shade of grey.) After seeing the image several times, and understanding that they are the same shade of grey, it becomes -harder- to see them as different shades of grey, just as initially it is hard to see them as the same shade of grey. What in the referenced explanation explains that, and why isn't that precisely relevant to Rand and 'what is' based on what 'we perceive?'



Share this post

Link to post
Share on other sites


You may be familiar with the perceptual anomaly in gray-tone perception known as the Mach-Bands illusion.'>* That one is hardwired and is fundamentally explained by lateral-inhibition wiring in the retina. It has to be present in all of our visual perception and in all animals having that pattern of wiring in the retina. In this case, we readily see a possible survival advantage to the anomaly in that the shading at the seam of two areas having different values of gray helps alert the viewer to the possibility of a 3D edge at the seam. That is, we think the Mach-band illusion helps animals, including us, detect edges, which can be significant for action.

That is not to say this mechanism of edge enhancement was selected for, without specific proof that it was. It may have just been attendant an engineering solution effecting some more fundamental exploitation of optics with the neuron possibilities at hand, which turned out to have as well this edge-detection advantage to a lot of animals. One nice thing about the Mach bands is that if you set them up in your presence, say, by using paint chips, a photo can be taken of them and published to show others, with the effect still showing. Have you ever seen a great big moon rising above the horizon and taken a picture of it? Very disappointing photo. Although the moon illusion evidently arises from processing higher up in the visual system, it cannot be eliminated from our natural perception (thank goodness) and is evidently hardwired.

There is some research on similarity and identity in cognitive development in a'>section of my “Capturing Concepts” you may find of interest.


Two more reviews of Ayn Rand Explained: a longer'>one from a fellow sympathetic with Albert Ellis (though not with the politics of Ellis), which is fairly favorable; and a short favorable'>one.

Share this post

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.