There were two key questions I asked Irving [Kahn] via his grandson. One was, “If you could share a single piece of financial advice that you’ve learned over your life that is absolutely invaluable, what would it be?” [Irving] came back via his grandson. He did an extraordinary job, interviewed him over days about these things. Came back and said, “Safety.” He said, “The #1 thing is paying attention to the downside.” He said, “There are all these people. It’s like they’re on a horse and they can gallop very fast, but do they know what direction they’re going in?” It was kind of this fascinating insight that sounds really banal and prosaic in some ways, but this is coming from a guy of 108 who managed to survive the crash of 1929, World War II, Vietnam, any number of crises and crashes. When I started to think about that, this is one of those ideas that if you truly internalize it, it actually has an enormous impact on you.Qtd in The Manual of Ideas, March 2017.
He said, for example, “You’ll find that if you make reasonable gains and avoid disastrous losses, you’ll outperform all of your gambler friends.”