This is an extraordinary example of what might be called “functional seeing”. Compare checker square A and square B-

Although you should not believe this just on the basis of what you see, squares A and B are exactly the same shade of gray. You can confirm this in a graphics program (like photoshop). The fact that you see the squares as different shades of gray strongly suggests that your brain has evolved to tell you more about shadows than about the particular shades of colors. Why? Because representing shades of color as such is something that only an artist needs to do; it has very little survival value (unless you happen to be one of those lucky artists who gets paid for discriminating colors). On the other hand, distinguishing shadows is an important aspect of seeing objects in a natural world, and seeing objects is crucial to survival. One other thing: the fact that you can’t see the two squares as having the same color even after you know that they do is proof of the visual system’s “modularity” or “informational encapsulation”: vision is highly resistant to modification by belief or knowledge. Believing is not seeing.

Thanks to Edward H. Adelson at MIT for making this image available.

It’s not often that you get two justices of the Supreme Court with such different points of view informally debating on national television, but that’s just what you got with C-SPAN’s recent America & The Courts hour. Justices Scalia and Breyer squared off on pros and cons of Originalism – roughly, the view that Supreme Court justices should always interpret and apply the clauses of the constitution exactly as the founders would have, at least to the extent that this can be determined. I disagree with Scalia on Originalism, because I fail to see why the interpretations of the founders – who, after all, were just humans, not gods – should be favored over the interpretations of present supreme court justices, who have the benefit of history and hindsight, and so probably have a wider and wiser perspective on how to apply to present circumstances the values enshrined in the constitution. However, in the past I have been impressed by Scalia’s ability to argue for his judicial philosophy. So I was happy to see that Breyer could keep up with him quite well, arguing at least as effectively for his approach. A rarity on TV these days: intelligent and relevant programming.

You can watch the hour online here.