Featuring Richard Elwes. See for Brilliant and 20% off their premium service & 30-day trial (episode sponsor). More links & stuff in full description below ↓↓↓ Numberphile videos about big numbers: Gödel's Incompleteness Theorem: Richard Elwes at the University of Leeds: Or: His books: On the Restricted Ordinal Theorem (by Goodstein): ~hart/onderwijs/verzamelingenleer/materiaal/ Accessible Independence Results For Peano Arithmetic (by Kirby and Paris): Patreon: Numberphile is supported by Jane Street. Learn more about them (and exciting career opportunities) at: NUMBERPHILE Website: Numberphile on Facebook: Numberphile tweets: Subscribe: Video by Brady Haran and Pete McPartlan Numberphile T-Shirts and Merch: Brady's videos subreddit: Brady's latest videos across all channels: Sign up for (occasional) emails: