"Expertise in Expert Systems"

When I arrived at CMU in 1982, expert systems were all the rage:  find an expert, encode the rules by which he makes decisions into a computer and presto-magic we can replace humans with droids.  That vision didn't quite work out.  Then came the statisticians with their focus on formal probabilistic models.  Now the neural-network guys are telling us that we can dispense with both the experts and the models, and that all we need is some data and the chain rule.