I think a lot of people in this thread are overstating the suspicion of outsiders. International trade has existed for thousands of years. There was even limited tourism in the middle ages. It would be rare to encounter people that you couldn’t communicate with, but I don’t think you’d be automatically sacrificed.

I’m in London, so would fare better than most as they would definitely be familiar with outsiders. That said people in many of the old European cities would likely be able to blag their way to local universities. Oxford definitely already existed 650 years ago so I’d start by heading there.

I think all scholarly writing was in Latin at the time, so I’d need somebody to translate, but (with luck) I could move maths on a couple of hundred years. I reckon I could get basic electricity going too. Obviously the more you said upfront the more suspicious people would be, but if you drip-fed knowledge over a few years, trying to let the steps rest upon each other you could probably share a lot of what we know today.

Isn’t that a ‘necessary but not sufficient’ condition though? I’m thinking principally of the struggles in Zimbabwe here.

I love how memes (in the Dawkinsian sense) work. Lots of people have enjoyed this, but I can imagine this being quoted as the original is lost to the sands of time.

Young people everywhere thinking that Aquaman was someone who just bought failing assets from everyone.