of writing down thousands of rules manually would be a sure way to build truly intelligent machines. So, domain experts were hired to try to distill their thought processes into numerous rules. This idea, called expert systems, drove the AI hype in the ’80s. One of the big issues with this approach was that it was very difficult and impractical—teaching a machine to perform any task required a lot of rules. Also, experts had a hard time describing their intuitive reasoning as a set of inflexible, robotic rules, and different experts often disagreed.
