I'd be willing to bet that at one point or another, Wolfram likely mentions all of these prior works. One also has to realize that Wolfram actually started thin

I'd be willing to bet that at one point or another, Wolfram likely mentions all of these prior works. One also has to realize that Wolfram actually started thinking about this whole thing much earlier (35 years or so ago) than many of these other authors, and wrote papers about such. That isn't to say these other works aren't original, or that there wasn't art prior to even then. Finally, Wolfram throughout the book notes that his ideas aren't new or original in whole - he actually belabors on this repeatedly (so much so, it became tiring for me to read it - it seemed like it was every other page).