This paper details the reconstruction and execution of the Logic Theorist (LT), considered the first artificial intelligence program, originally created in 1955-1956. The authors built a new IPL-V interpreter in Common Lisp and faithfully reanimated LT from code transcribed from a 1963 RAND technical report. The reanimated LT successfully proved 16 of 23 theorems from Principia Mathematica, consistent with the original system's behavior. This work demonstrates "executable archaeology" as a method for understanding early AI systems, highlighting the challenges and insights gained from reconstructing and running historical code.
- Raph Levien, who is an expert in Rust and rendering on GPUs, who founded Advogato, and who designed Inconsolata, a great monospace font. His talk's title is *I Want a Good Parallel Language*.
- Jeff Shrager will give a talk on reviving early AI programs like ELIZA and IPL-V. His talk's title is *RetroAI: Reanimating the Earliest AIs in the Lost Languages that Predated Lisp*.
This GitHub repository contains a re-implementation of the IPL-V programming language and the Logic Theorist (LT) program. It includes the original code transcribed into a TSV format and converted to Lisp, along with documentation and debugging tools.
Information Processing Language (IPL) is a programming language created by Allen Newell, Cliff Shaw, and Herbert A. Simon at RAND Corporation and the Carnegie Institute of Technology in 1956. IPL introduced concepts like list processing, dynamic memory allocation, recursion, and cooperative multitasking. It was an assembly language for manipulating lists and influenced several early AI programs. However, it was soon replaced by Lisp due to its more powerful features and simpler syntax.