Comment by Closi

> I’m also unaware of a ground truth against which “correct facts” could even be trained for..

Seems like there are quite a few obvious possibilities here off the top of my head. Ground truth for correct facts could be:

1) Wikidata

2) Mathematical ground truth (can be both generated and results validated automatically) including physics

3) Programming ground truth (can be validated by running the code and defining inputs/outputs)

4) Chess

5) Human labelled images and video

6) Map data

7) Dependent on your viewpoint, peer reviewed journals, as long as cited with sources.