I realise this isn't a very helpful comment in itself, but I hope Hacker News comments don't go the way Reddit comments have, where they routinely post and upvo

I realise this isn't a very helpful comment in itself, but I hope Hacker News comments don't go the way Reddit comments have, where they routinely post and upvote content that's already in the linked article (usually because few people read beyond the title). In this case - just reposting the Feynman video - it's fine, but in other cases it leads to a lot of uninformed or unnecessary discussion, sometimes speculating on some hypothetical that the article already answers.