(Note, I originally gave this 3 stars but now would call it 2, although the system won't let me change that. See Edit note at the end.) The book contains about 90 or so optical illusions. The illusions are mainly along the lines of things that look curved when they are actually straight, things like look different sizes when they are a really the same size if you measure them, and similar. Many of these illusions will be like ones you've seen before if you are into this sort of thing, but there are some new variations I hadn't run across before.
The book is nicely illustrated and pretty to look at. However, it gets only an "average" rating for two reasons:
1. There's not a single word of explanation in the entire book as to *why* the illusion occurs and why the eye is fooled. According to the "about the author" page, the author is "the world's leading authority of visual and other types of sensory illusions". Given that, I would've hoped for at least a little bit of explanation or discussion of the illusions. Instead, you get just the photos, each accompanied by one or two sentences along the lines of "Does the one thing look larger than the other? Check your answer."
I went to the author's website (he is associated with Harvard and formerly associated with Caltech) in the hopes of more info. But that is mostly an extended resume for the author and list of his books, speaking engagements, etc. (Although there's a somewhat interesting section devoted to several Escher-like artists, with some movies of interviews of some of the artists.)
2. Many of the illusions are just very small variations on the exact same illusion, rather than being something new and different as I had hoped.
Overall, certainly not a worthless book and quite pretty. But probably a lot more interesting to someone who's never seen these types of illusions at all before (or to a child) than to any adult who has any previous familiarity with the topic.
Edit: Also, there is at least one of what appears to be an out and out mistake. One page shows what is supposed to be the "Wundt Illusion". It pictures two seemingly identical profile views of the drawing of a woman's head and torso, and asks "Does the figure on the left appear to be smaller than the figure on the right?". Well, the answer is "No, they appear to be the same size and they actually are the same size when measured." Not only that, but even if they appeared to be different this wouldn't be an example of what is normally called the "Wundt" illusion (I looked it up), which has to do with lines looking bowed when they are really straight.
Yikes, make that 2 errors so far. One page asks "Do all 3 squares appear to be the same size?" Well, the answer is "Yes, they do (and they are when measured) and they also aren't squares- they are clearly rectangles (both in perception and when measured."
For mistakes/ poor editing, I would call this a 2 instead of a 3 if I was able to change the # of stars.