While I was reading it I got the impression that it was pointing at common mistakes, not just demonstrating correct behavior -- so the protagonist first sets the probability to zero based on naive trust (and because the player is not yet ready to handle an explicit model of the correctness of statements), but this gets corrected later in a realistic way.

If the game made a point of this sort of thing, it would give the (good!) impression that all examples in the game are approximations which need to be refined quite a bit to account for real-life details.

In hindsight, I see it's not doing this effectively. Perhaps when she finds out the kid was wrong she's like "Whoops! We just gave a probability of zero to something which then immediately happened!! That's just about as wrong as you can possibly get. We'd better account for that in our model." Or, something to that effect.