Reviving the World’s First Chatbot: ELIZA Returns

Scientists have successfully brought the world’s first chatbot, ELIZA, back to life. Despite being dormant for decades, ELIZA still functions as it originally did. According to LiveScience, while chatbot development surged in popularity after the 2022 release of ChatGPT, the roots of this technology trace back much further. On December 21, 2024, researchers completed the revival of ELIZA, marking a significant milestone in computing history.

The journey to resurrect ELIZA began in 2021, when researchers rediscovered its original code. Over the next few years, they meticulously reconstructed its structure, culminating in a detailed report published recently on arXiv. ELIZA was originally created between 1964 and 1967 by Joseph Weizenbaum, a computer scientist at MIT. Built using the MAD-SLIP programming language on the Compatible Time-Sharing System, ELIZA was groundbreaking for its time and is widely regarded as the first-ever chatbot.

Weizenbaum gave ELIZA the persona of a psychotherapist, creating a program that mimicked human conversation to an impressive degree for its era. Even Weizenbaum himself became captivated by interacting with it. In the years following its debut, programmers adapted ELIZA to different languages and platforms. Notably, in 1977, a BASIC version of ELIZA was featured in Creative Computing magazine during a period of explosive growth in personal computing, spurred by devices like the Apple II and Commodore PET.

Although the BASIC versions proliferated, the original MAD-SLIP code was thought to be lost—until its partial rediscovery. Despite its incomplete state, researchers painstakingly rebuilt ELIZA, ensuring it worked once again. While primitive compared to modern AI tools like ChatGPT, ELIZA’s revival serves as a testament to the ingenuity and vision of early computing pioneers.