Hat trick - the experiment

The motivation for tackling this simple puzzle was that research in knowledge engineering usually involves some informal way of knowledge elicitation, where knowledge from a human expert is made explicit so that it can be formalized into a model. My supervisor thought it would be a good idea to follow this process to the letter.

To this end, a student was invited to solve the puzzle, reasoning loud, with a tape recorder registering the process. It was interesting to find out how the process of explicitly verbalizing the reasoning seemed to interfere with the reasoning itself: once or twice, our subject muttered phrases like "Okay, so suppose I'm wearing a white hat, then... erm... nonono, what did I just say?" Apart from small glitches, the reasoning was in line with my expectations, and the transcript obtained was neatly translated into a logical model, involving meta-level reasoning.

I was proud to find that the resulting paper was accepted by the European Knowledge Acquisition Workshop '91 (EKAW'91), which took place in Crieff, Scotland. For the first time in my life, I was going to travel abroad.