The Fifth-Generation Computer was to be the end result of a massive government/industry research project in Japan during the 1980s, which aimed to create an "epoch-making computer" that would leapfrog more evolutionary designs by using the Prolog programming language to create a desktop system with supercomputer-like performance and usable artificial intelligence capabilities.

The term "fifth generation" was intended to convey the system as being a leap beyond existing machines. Computers using vacuum tubes were called the first generation, transistors and diodes the second, ICs the third, and those using microprocessors the fourth. Whereas previous computer generations had focused on increasing the number of logic elements in a single CPU, the fifth generation, it was widely believed at the time, would instead turn to massive numbers of CPUs for added performance.

Throughout these multiple generations since the 1950s, Japan had largely been a follower in terms of computing advancement, building computers following US and British leads. The Ministry of International Trade and Industry (MITI) decided to attempt to break out of this follow-the-leader pattern, and in the mid-1970s started looking, on a small scale, into the future of computing. They asked the Japan Information Processing Development Center (JIPDEC) to indicate a number of future directions, and in 1979 offered a three-year contract to carry out more in-depth studies along with industry and academia. It was during this period that the term "fifth-generation computer" started to be used.

The primary fields for investigation from this initial project were:

  • Inference computer technologies for knowledge processing
  • Computer technologies to process large-scale data bases and knowledge bases
  • High performance workstations
  • Distributed functional computer technologies
  • Super-computers for scientific calculation

The project imagined a parallel processing computer running on top of massive databases, as opposed to a filesystem, using a logic programming language to access the data. They envisioned building a prototype machine with performance between 100M and 1G LIPS, where a LIPS is a Logical Inference Per Second. At the time typical workstation machines were capable of about 100k LIPS. They proposed to build this machine over a ten year period, 3 years for initial R&D, 4 years for building various subsystems, and a final 3 years to complete a working prototype system. In 1982 the government decided to go ahead with the project, and established the Institute for New Generation Computer Technology (ICOT) through joint investment with various Japanese computer companies.

So ingrained was the belief that parallel computing was the future of all performance gains that the Fifth-Generation project generated a great deal of apprehension in the computing field. After having seen the Japanese take over the consumer electronics field during the 1970s and apparently doing the same in the automotive world, the Japanese in the 1980s had a reputation for invincibility. Soon parallel projects were set up in the US as the Microelectronics and Computer Technology Corporation (MCC), in England as Alvey, and in Europe as the European Strategic Program of Research in Information Technology (ESPRIT).

Over the next ten years the Fifth-Generation project ran into one difficulty after another. A primary problem was that their selected language, Prolog, did not support concurrency, and therefore they had to develop their own language for their multi-CPU goals. This never happened cleanly, and in fact a number of languages were developed, all with their own limitations. Another problem was that existing CPU performance quickly pushed through the "obvious" barriers that everyone believed existed in the 1970s, and the value of parallel computing quickly dropped to the point where it is today used only in niche situations. Although a number of workstations of increasing capacity were designed and built over the project's lifespan, they generally found themselves soon outperformed by "off the shelf" units available commercially.

The Fifth-Generation Computer was constantly on the wrong side of technology curve in software as well. Over the period of it's lifespan Apple Computer introduced the GUI to the masses, the internet made locally-stored large databases a thing of the past, and even simple research projects constantly provided better real-world results in data mining, Google being a good example. Moreover the project found that the promises of logic programmer were largely illusitory, and they ran into the same sorts of limitations that earlier artificial intelligence researchers had, albiet at a different scale. Repeated attempts to make the system work after changing one language feature or another simply moved the point at which the computer suddenly seemed stupid. In fact it can be said that the project "missed the point" as a whole. It was during this time that the computer industry moved from hardware to software as a primary focus. The Fifth Generation project never made a clean separation, feeling that, as it was in the 1970s, hardware and software were inevitably mixed.

By any measure the project was an abject failure. At the end of the ten year period they had burned through over 50 billion yen and the program was terminated without having met its goals. The workstations had no appeal in a market where single-CPU systems could outrun them, the software systems never worked, and the entire concept was then made obsolete by the internet.

External links:

What is FGCS Technologies?
- at the main project site, promotes a seemingly successful project. Includes pictures of prototype machines
Fifth Generation Computing Conference Report
The fifth generation: Japan's computer challenge to the world
- 1984 article from Creative Computing