The collector of quotes, quirks, and philosophical beefs. Diogenes Laertius (fl. 3rd century CE) didn’t invent philosophy — he just made sure no one forgot who said what, when, and with what level of snark. His Lives and Opinions of Eminent Philosophers is part gossip column, part archive, and part intellectual fanfiction. He’s not always accurate, but always entertaining. Without him, we’d know a lot less — and miss out on some truly bizarre philosopher origin stories.