> just find the most probable word that follows next
Well, if in all situations you can predict which word Einstein would probably say next, then I think you're in a good spot.
This "most probable" stuff is just absurd handwaving. Every prompt of even a few words is unique, there simply is no trivially "most probable" continuation. Probable given what? What these machines learn to do is predicting what intelligence would do, which is the same as being intelligent.
>Probable given what?
The training data..
>predicting what intelligence would do
No, it just predict what the next word would be if an intelligent entity translated its thoughts to words. Because it is trained on the text that are written by intelligent entities.
If it was trained on text written by someone who loves to rhyme, you would be getting all rhyming responses.
It imitates the behavior -- in text -- of what ever entity that generated the training data. Here the training data was made by intelligent humans, so we get an imitation of the same.
It is a clever party trick that works often enough.