Norvig's classic AI textbook, liberated under MIT license

What it does

This repository houses the complete text and source code of Peter Norvig’s 1992 book Paradigms of Artificial Intelligence Programming: Case Studies in Common Lisp. After the copyright reverted to the author, Norvig released it under the MIT license. You get the full book as markdown files and generated ebooks, alongside every line of Common Lisp from the original text—GPS, Eliza, Prolog interpreters, Scheme compilers, and more—organized by chapter.

The interesting bit

It is rare for a landmark technical book to become fully open source with the author’s blessing. The code is not merely illustrative; it includes working interpreters and compilers built inside Common Lisp, including a tail-recursive Scheme interpreter with call/cc support and a Prolog compiler with peephole optimization.

Key highlights

• Full book text available as markdown, PDF, and epub releases, complete with Norvig’s retrospective and errata
• Runnable implementations of classic AI programs: General Problem Solver, Eliza, symbolic math (Macsyma), and an Othello strategy engine
• Working Prolog interpreter and compiler, plus a Scheme interpreter and compiler, all written in Common Lisp
• Interactive code collection with an example runner and tutor utility
• Listed among the most influential books for programmers, with 7,468 stars suggesting it remains relevant

Caveats

• The OCR-derived text file (PAIP.txt) contains many errors; the markdown and Safari-sourced epub are cleaner
• There is no single application to run; the code is a collection of discrete chapter files meant for interactive exploration
• The custom requires loader may need tweaking for your specific Lisp system

Verdict

Worth bookmarking if you study Lisp, language implementation, or AI history. Skip it if you need modern machine-learning libraries or a batteries-included framework.