paip-lisp

This repository is the open-source companion to a textbook called "Paradigms of Artificial Intelligence Programming: Case Studies in Common Lisp," written by Peter Norvig and originally published in 1992. The author reclaimed the copyright and released everything here under an open license. The book appears on several lists of the most influential texts for programmers and covers both the Lisp programming language and foundational ideas in artificial intelligence.

The repo contains two main things: the full text of the book in various formats, and all of the Lisp code from its chapters. The book is available as scanned PDFs of older print editions, as automatically generated ebooks, and as a set of Markdown text files for each chapter. If you want to read it digitally, the releases section of the repository is where the downloads live.

The code covers a wide range of classic AI topics spread across 25 chapters. Early chapters build simple programs like a version of Eliza, the 1960s chatbot that mimics a therapist, and a general problem solver that tries to figure out sequences of steps to reach a goal. Later chapters get into logic programming, expert systems, natural language grammars, game-playing strategies for Othello, and how to build a Lisp compiler. Each chapter's code is in its own file, making it straightforward to read alongside the corresponding chapter.

Common Lisp is an older programming language that was central to AI research in the 1980s and 1990s. You do not need to already know it to benefit from the book, but some programming background helps. The code files are meant to be read and run together with the text, not as standalone tools.

This is primarily a learning resource and historical archive rather than a library you would pull into a project.