A stock market veteran’s view on the AI bubble

Two-sigma statistical definition

Grantham defines bubbles as 2-sigma events (two standard deviations from trend) that occur roughly every 36 years, confirming the market entered bubble territory four to five years ago and exhibited classic "super bubble" characteristics by late 2021.

The ChatGPT revival

After the 2022 crash saw the S&P 500 fall 25% and growth stocks drop 35%, the introduction of ChatGPT triggered an extraordinary rally fueled by massive AI capital expenditure that prevented a recession and reinflated valuations beyond the 2021 peak.

Railroad boom as the only parallel

The AI investment surge is unprecedented in modern markets, comparable only to the 19th-century railroad bubble where transformative technology attracted excessive capital that bankrupted early investors despite fundamentally changing the economy.

Amazon's 92% decline precedent

During the dot-com bust, Amazon fell 92% over three years despite the internet's genuine promise, illustrating how even revolutionary technologies produce catastrophic early investor losses before delivering long-term benefits.

End of the monopoly era

For two decades, the Magnificent 7 operated as non-competing monopolies in separate sectors, but they are now simultaneously pivoting to dominate AI, transforming from cooperative price-setters into aggressive "fight to the death" competitors.

Inevitable margin compression

These "sharp-edged" capitalists are engaging in unprecedented spending races projected at $200 billion annually, which will inevitably erode profit margins through classic capitalist competition and validate regression to the mean.