Down the rabbit holes in the PHP is the Toyota Corolla of Programming Languages article, I learned about the Fifth Solvay Conference. Never heard of it. It seems like in most eras, it would take a couple centuries worth of thinkers to put so many brilliant minds in the same room as were at the one conference.
https://rarehistoricalphotos.com/solvay-conference-probably-intelligent-picture-ever-taken-1927/
https://en.wikipedia.org/wiki/Solvay_Conference#Fifth_conference