Video and slides synchronized, mp3 and slide download available at URL http://bit.ly/2sxCk8u. Paul Sztorc talks about why the oracle problem is so hard (specifically, the historical evolution of failures, from API, to clearnet website, to darknet website, to multisig escrow, to judicial "competition", to Ethereum/Augur, and why they fail), and the basics of blockchain ("blockchain as immortal software", ledger "rents", revenge of "the idea guy"). Filmed at qconlondon.com. Paul Sztorc has been interested in Bitcoin since 2012, and interested in prediction markets his entire adult life. After InTrade.com was forced to close in 2012, he set out to immortalize the institution using blockchain technology. He was hired privately in January 2015 to work on Bitcoin full time, and has worked for the startup Bloq, Inc. since March 2016.