We Asked Jeremy Grantham Why AI Won’t Boost Profits — and What It Will Do Instead

Selective bullishness defines career

Grantham rejects the "perma bear" label by citing two decisive bullish calls: his 1982 recommendation to buy at 7x earnings and his March 2009 essay "Reinvesting When Terrified" published the day the S&P hit 666, urging investors to buy during the panic.

Differentiating crisis severity

He emphasizes reserving extreme language like "abandon ship" only for high-confidence warnings, such as his July 2008 letter that preceded a 50% crash in emerging markets, distinguishing these from ordinary valuation concerns.

Historical cycles govern returns

Grantham states that everything in markets mean reverts—from P/E ratios to sector performance—as abnormal profits attract competition and losses deter capital until equilibrium returns.

The Mag 7 monopoly anomaly

A handful of tech giants have temporarily escaped mean reversion through winner-take-all dynamics and uniquely lax antitrust enforcement since 2000, creating global price-setting monopolies that slow GDP growth despite boosting their own margins.

Concentration stifles growth

While monopoly profits surge for dominant firms, overall economic growth has actually slowed because increased inequality and reduced competition characteristic of monopoly power depress system-wide GDP expansion.

Temporary competitive advantage only

Early AI adopters will enjoy wider profit margins initially, but this benefit will vanish as the technology becomes universal, transitioning from a competitive edge to a basic operational cost.

No lasting margin expansion

Grantham asserts AI will not raise aggregate corporate profit margins because once all competitors implement it, the technology merely becomes another cost of doing business with normalized returns on capital, similar to how mini-computers became standard in asset management.

Massive uncertainty remains

Unlike previous technologies, AI generates vast disagreement even among Nobel laureates about whether it will create utopia or existential risk, making its ultimate economic impact impossible to predict with confidence.

Brutal competition ahead

Grantham warns that markets are transitioning from a monopoly world to one of "brutal competition" where aggressive, cash-rich tech giants are heading "into each other's teeth," predicting "blood in the streets" as they battle for dominance.

Fight human cognitive biases

He advises investors to consciously combat humanity's tendencies to ignore unpleasant news and avoid long-term thinking, which are hardwired behavioral traps that lead to poor investment decisions.