That checkered shadow illusion . . .

http://web.mit.edu/persci/people/adelso ... demos.html

There's some animated sequences that demonstrate the same thing.

Hey, thanks. I was thinking of looking for that also.

I learned something new in this chapter. How our evolutionary heritage has influenced us to maintain beliefs in spite of the anomalies we might encounter. It makes sense!

This will seem like either a naive viewpoint or a quibble about semantics, but I don't necessarily see any cons to our evolutionary heritage. I mean the fact that we have such and such abilities and not others is just the way it had to be for us to adapt for survival. That our 'design' is not in every way so intelligent doesn't mean that, for example, our spinal structure is a 'con.' It obviously served a purpose in creatures like us succeeding. It's much the same for visual perception inconsistencies and cognitive biases. They exist, but unless we can realistically expect that a 'perfect' creature could come about, the only criterion we should use to evaluate our evolutionary heritage is whether our kind survived, which we did in spades. We have what we could call weaknesses (such as our cognitive biases), but since we wouldn't have (would we?) the cognitive strengths without them, it doesn't seem that pro/con is the way to look at what we are.

Well, maybe at some far future point if our numbers decrease drastically due to our own actions (or inactions), we'll then be able to accuse some trait of being a culprit.

Much like some aspects of physics that require a frame of reference, I think weighing our evolutionary heritage also requires one. If you weigh it against the "ideal" sentient creature, we have weaknesses. If you weigh each individual against the average, a bell curve will fill the spectrum. If you weigh us against an ape, our mental portfolio is all very strong. There is also the purpose for which our minds are weighed. For example, if we are contrasted for our ability to procreate, we are successful. If it is our speed at simple math, a computer performs better than us. At pattern recognition, we are without equal. At discovering the truth of our reality, we have a few weaknesses.