Self-play works for Go, because the "world" (for lack of a better term) can be fully simulated. Human language talks about the real world, which we cannot simul

Self-play works for Go, because the "world" (for lack of a better term) can be fully simulated. Human language talks about the real world, which we cannot simulate, so self-play wouldn't be able to learn new things about the world. We might end up with more regularised language, and a more consistent model of the world, but that would come at the expense of accuracy and faithfulness (two things which are already lacking).