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.
The original 1965 chatbot restored on the world's first time-sharing system, ELIZA, created by Joseph Weizenbaum at MIT in 1964-6, is running again on a reconstructed version of MIT's CTSS, running on an emulated IBM 7094.
