Jeremy Grantham on AI, Bubbles and Why Mean Reversion Lives On

Excess Returns · May 16, 2026 · 1h 4m

Jeremy Grantham joins Excess Returns to discuss The Making of a Permabear, mean reversion, market bubbles, AI, the Magnificent 7, and the long-term lessons investors can take from his career at GMO. We cover why he rejects the simple “permabear” label, how he thinks about valuation and bubbles, why AI may be both transformative and dangerous for investors, and why long-term thinking is so hard but so essential.

The Making of a Permabear: The Perils of Long-term Investing in a Short-term World

https://groveatlantic.com/book/the-making-of-a-permabear/

GMO

https://www.gmo.com/americas/

Grantham…