Plate III. The Cathedral of Rules, 1980–1987
The Cathedral of Rules

Knowledge, written down as rules, becomes a product.
Expert systems captured specialists’ judgement as thousands of IF–THEN rules. XCON configured computer orders at DEC; Japan launched its Fifth Generation project; a market grew for specialised LISP workstations.
Meanwhile a quieter 1986 paper popularised backpropagation for training neural networks. It would take twenty years and far more data and compute for that seed to grow.
Events
- XCON goes to work at DEC (1980)
- Japan’s Fifth Generation project (1982)
- Cyc begins encoding common sense (1984)
- Backpropagation, popularised (9 Oct 1986)
- The LISP machine market collapses (1987)