Among psychologists, there’s a term for that: theory of mind. This hallmark of social intelligence allows us to infer the inner reality of another person’s mind based on their speech and behavior, as well as our own knowledge of human nature. It’s the intuitive logic that tells you Ding Liren felt elated, not melancholic, after winning the World Chess Championship this month. It’s also an essential ingredient for moral judgment and self-consciousness.

In February, Stanford psychologist Michal Kosinski made the stunning claim that theory of mind had emerged spontaneously in recent generations of large language models like ChatGPT, neural networks which have been trained on enormous amounts of text until they can generate convincingly human sentences.

“If it were true,” says Tomer Ullman, a cognitive scientist at Harvard, “it would be a watershed moment.” But in the months since, Ullman and other AI researchers say they’ve confounded those same language models with questions a child could answer, revealing how quickly their understanding crumbles.