Comment by program_whiz

And when you think, how do you know which word will appear next in your mind? Or does your system 2 thinking seem to emerge as a spontaneous stream of words/thoughts?

I actually think that AI has little to do with the brain / human intelligence, but in this regard, human thinking is also spontaneous, where the next thought just seems to emerge from the combined effect of all inputs to your brain (including the memory of recent thoughts).