In this week's Five Good Questions, we're interviewing Lord John Browne about his book Make, Think, Imagine. John Browne trained as an engineer, was CEO of BP from 1995 to 2007 and remains an influential leader in the energy business. He is Chairman of the Crick Institute, a Fellow of the Royal Society, past President of the Royal Academy of Engineering and former Chairman of Tate. He is a collector of antique books and art and the author of four previous books, including The Glass Closet: Why Coming Out is Good Business. Five Good Questions: 1. Do you have a sense that much of cutting edge technology relies on intervention into complex, nonlinear systems and fattens the probability tails of undesirable outcomes? Said more simply, does technology invite more black swans? 2. What’s the one new tech on the horizon that you’re most excited for? 3. How was the stirrup such a powerful invention and what does it tell us about the future of technology? 4. How did gunpowder ironically lead to greater peace in the world? 5. Investors like Warren Buffett have borrowed the engineering principle of margin of safety for their investment processes. What’s another concept from engineering that might also be useful for us?