IBM’s Project Debater should be congratulated on its success – matching two seasoned humans in debate. But on closer inspection, and contrary to media euphoria, it shows how much further AI-based natural language has to go before it really can match people, at least at the highest level. In some ways it flattered AI by coming out with what superficially sounded like compelling arguments, but were more like reasonable efforts in a school debating society. It represented significant progress but also reminded us of challenges like approaching absolute zero or reaching the speed of light – where it is those last few degrees or meters per second that are hardest to achieve. It is not fair to call media reaction…