Lesson 222 of 1570
The Second Winter: Expert Systems Collapse
The 1980s AI boom ended when expert systems hit a wall and specialized Lisp machines went obsolete.
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What this lesson covers
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The main moves in order
- 1The Boom Ends Around 1987
- 2second AI winter
- 3Lisp machines
- 4expert system collapse
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Section 1
The Boom Ends Around 1987
The mid-1980s AI boom was real. Expert systems saved money at blue-chip firms, and hundreds of startups sold knowledge-engineering tools. Specialized hardware called Lisp machines, sold by Symbolics and LMI, ran the software at premium speeds. The market for AI hardware and software reportedly passed a billion dollars.
Then it collapsed. Around 1987 to 1988, cheaper general-purpose workstations from Sun and later PCs running LISP matched Lisp machine performance at a fraction of the cost. The specialized hardware industry died within a few years.
What failed
- Brittleness: systems broke on cases outside their rule set
- Maintenance cost: every update needed a knowledge engineer and an expert
- No learning: the system could not improve from experience
- Japan's Fifth Generation project ended without dominating anything
By the early 1990s, the term AI carried enough stigma that many researchers rebranded. Machine learning, intelligent agents, and informatics all emerged partly as escape hatches from a tainted word.
“By the late 1980s, the business press was speaking of an AI winter.”
Key terms in this lesson
The big idea: hand-crafted knowledge does not scale. The next era of AI would have to learn from data, because humans could not write enough rules fast enough.
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