Seconding this question.

I found Synergetics in the local library when I was in high school, was duly impressed by Arthur C. Clarke's endorsement on the cover, but didn't understand much at all about the book. I was too young to tell if the book was obvious math crankery or not back then, but the magnum opus style of Synergetics combined with it being pretty completely ignored nowadays makes it look a lot like an earlier example of the type of book Wolfram's A New Kind of Science turned out to be.

Still, I'm curious about what the big idea was supposed to be and what did people who seriously read the book thought about it.

ETA: For the curious, the whole book available is online.