Paper short abstract:

Despite being considered a major language for AI in the 80s, Prolog is now viewed as a minor language. Our analysis correlates its decline with the Japanese Fifth Generation Computer project. This case prompts a discussion on the broader impact of unmet promises in AI on foundational technologies.

Paper long abstract:

The Prolog programming language, conceived in 1972 at the University of Marseille, introduced the ‘logic-programming’ paradigm well-suited for symbolic artificial intelligence (AI) applications (Colmerauer 1993). In 1982, Prolog was selected as the main programming language for an ambitious Fifth Generation Computer Systems (FGCS) project led by the Japanese government which triggered the “First AI Arms Race” (Garvey 2020) in the USA and Europe. Despite its popularity in the 1980s, Prolog faded into obscurity in the 1990s, with actors' narrative linking its fall to that of the FGCS project (van Emden 2010).

To what degree can Prolog be considered a collateral victim of the FGCS project? How is the scientific destiny of languages determined by the institutional and industrial framework of the projects that rely on them?

We conducted a comprehensive analysis using both quantitative and qualitative approaches. We gathered metadata from hundreds of articles in the ACM Digital Library and cross-referenced this data with proceedings and field reports from the FGCS project, supplementing our findings with testimonies from researchers involved at the time.

Findings reveal a correlation between Prolog's publication volume and the perceived state of the FGCS project. Surprisingly, only a small fraction of Prolog publications were directly associated with fifth-generation computers; instead, Prolog found its stronghold in expert systems and database applications. Irrespective of its practical applications, Prolog became indelibly linked with the Japanese initiative.

Discussing the Prolog case aims to open a dialogue on the impact of unrealistic techno-scientific promises (Joly 2013) in AI on underlying technologies.