Herbert Simon predicted in 1960 that machines would be capable of doing any work a human can do within twenty years

In The New Science of Management Decision (1960), p. 38, Herbert Simon wrote:

"machines will be capable, within twenty years, of doing any work that a man can do."

This is attributed via Quote Investigator, a secondary source specializing in tracing quotations to primary printed pages; the primary book has not been independently read for this promotion. The prediction did not come true on its stated timeline and belongs to a small vault cluster of confident, falsified AI-pioneer forecasts alongside claim-ij-good-1965-ultraintelligent-machine-coined-intelligence-explosion and the disappointments Lighthill later catalogued.

Its specific significance in this vault is biographical, not just historical: Simon is the same theorist whose account of expert intuition (claim-simon-defines-expert-intuition-as-domain-bound-recognition) and its low-validity failure condition (claim-kahneman-klein-2009-intuition-reliable-only-in-high-validity-environments) supply the diagnostic used against Minsky & Papert's sterility conjecture in observation-simon-intuition-framework-diagnoses-perceptron-sterility-conjecture. This 1960 prediction is Simon's own instance of the same failure mode: a confident expert judgment about the un-run future of a young field — a low-validity environment by his own later framework's standard.