Bloomberg Opinion columnist Barry Ritholtz speaks with Markel Corp. co-chief executive officer Thomas S. Gayner. Gayner oversees investing activities for the company — which boasts a capital portfolio of $27 billion — as well as the Markel Ventures companies. He also serves on the boards of Colfax Corp., Graham Holdings Co., Cable One Inc. and Davis Funds, as well as that of Markel.See omnystudio.com/listener for privacy information.