[tarr11]

> Eventually we will pull the black ball out of the urn

What is this reference?

[jbreckmckye]

In the 18th and 19th centuries, gentlemen's clubs would vote whether to accept a new member. Each man would secretly place a ball in an urn, either black or white.

If your urn contained even one black ball, your membership was vetoed and your chances - ruined.

[realce]

I had forgotten the stem of this, thank you!

[realce]

https://mishayurchenko.me/2019/03/27/pulling-a-black-ball-fr...

[consumer451]

Seems like it might be this? https://nickbostrom.com/papers/vulnerable.pdf