When I was a kid I remember my elders telling me advice and conspiracy theories, just stuff about how the world works, and I, mostly internally, would roll my eyes or laugh. Now decades later many of those things seem to have been the truth ( obviously some couldn’t be further from it but that’s a different post)

but what sticks out to you as the thing that you just knew was such rubbish nonsense, and now years later you understand to be true.