The intellectual genealogy by which Herbert Simon's expertise research produced both the science of human development Ericsson pursued and the artificial intelligence program that now challenges it — two halves of a single mechanism that have now met.
Herbert Simon, who co-founded the field of artificial intelligence and predicted in 1957 that computers would beat humans at chess within a decade, mentored Ericsson at Carnegie Mellon in the late 1970s. Together they developed the technique of verbal protocol analysis — the rigorous use of think-aloud methods to study the cognitive processes underlying expert performance. Simon took the insights from expertise research and used them to build machines that could replicate expertise. Ericsson took the same insights and spent the rest of his life studying the human developmental process that expertise requires. The mentor built the machines. The student studied the humans the machines would one day challenge. This lineage crystallizes the present moment with a precision neither man could have anticipated: the two halves of a single research program have met, and the question of their relationship is the question the AI age most urgently poses.