For more than four decades, Jeremy Grantham has been one of the most contrarian voices in global investing. The co-founder of Boston-based asset manager GMO, he built his reputation warning about bubbles before they burst, from Japanese equities in the late 1980s to US tech stocks in 2000 and housing in the run-up to the global financial crisis. He joins this week’s Merryn Talks Money podcast with host Merryn Somerset Webb to discuss why he believes there's an artificial intelligence bubble and what happens if it bursts, his approach as a value investor and the lessons in his new book, The Making of a Permabear: The Perils of Long-Term Investing in a Short-Term World.