"Probably because there’s no free version online and it’s a pricey book. I got it for myself for Christmas and it’s well worth the price. It’s half AI book, half tutorial on Lisp programming and Lisp style. It’s a good read with lots of example programs written in good Lisp Style."<p>I'm sad he described PAIP this way. To me, PAIP isn't even so much about Lisp or AI as it is about how god damn awesome Peter Norvig is. I think my programming became much better after I studied his style.<p>Bottom line, PAIP makes you a better programmer even if you never intend to use Lisp for anything.<p>You should learn enough Lisp to read PAIP, in other words.