World’s first chatbot, ELIZA, resurrected from 60-year-old computer code

A small team of researchers from the U.S. and the U.K. has resurrected the code for a 60-year-old chatbot named ELIZA, believed to be the first electronic chatbot. In their paper posted to the arXiv preprint server, the team describes the code written in the 1960s by now-deceased MIT professor Joseph Weizenbaum.

In 2021, an archivist at MIT named Myles Crowley found printouts of computer code written by Weizenbaum in a box of some of his things. Subsequent review of the code showed that it was most of the original code for ELIZA, a chatbot the professor had coded. Back then, the term “chatbot” had not yet been invented; it was believed Weizenbaum thought of the program as an electronic therapist.

It was designed to be used as a request/response tool. A user would ask it a simple question and the system would reply back with a simple response and a follow-up question, similar to the way sessions with a human therapist are conducted.

Code for the original ELIZA was thought to have been lost, though code exists for other versions written by other programmers. After it was written in Lisp, it wound up on ARPAnet, and from there, slowly made its way to home computers, where it became popular as a sort of “friend” for tech-savvy users.

After finding the code, the researchers set to work trying to get it to run. First, they had to develop an operating environment; ELIZA was coded for an obsolete operating system. The researchers also found that the code needed cleaning, and in some cases, required them to write functions that were called by the code but not printed.

The team got the program running this past December. They ran it as it was intended, as a request/response tool, and found that it performed better than they expected. It was nowhere in the league of modern LLMs, of course, but they claim that it was fun.

One glaring bug would cause the program to crash if the user entered numbers, but the resurrecting team left it in for authenticity’s sake. They suggest that ELIZA should be considered a major part of computer history because it represents the first-known example of an electronic chatbot.

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