1
1
TL;DR: Legendary investors Ray Dalio and Jeremy Grantham are waving red flags. They believe the current AI stock frenzy looks eerily similar to the 1929 crash, the 2000 dot-com bubble, and the 2007 housing bubble. The "Four Horsemen of the Bubble Apocalypse" are showing up—and Wall Street’s own research teams are starting to agree.
On a recent episode of The Diary of a CEO podcast, host Steven Bartlett asked Ray Dalio—founder of Bridgewater Associates, the world’s largest hedge fund—what he thought about fellow investor Jeremy Grantham’s claim that we’re in "the biggest investment bubble in American history."
Dalio’s answer was blunt: "He’s right."
Grantham isn’t just any investor. He’s the co-founder of GMO and has a track record that reads like a highlight reel of bubble-spotting:
Important Callout: When someone with this track record says "bubble," smart money listens.
Grantham explains our current situation as a "bubble within a bubble":
| Phase | What Happened |
|---|---|
| Original Super-Bubble | Already inflating dangerously through 2021 |
| First Crack | S&P 500 fell ~25% (Jan–Oct 2022) |
| The Plot Twist | ChatGPT launches → "Mag 7" tech stocks lift the entire market on their shoulders |
| The Result | AI didn’t fix overvaluation—it "deferred it while making it larger" |
Grantham and financial historian Edward Chancellor found that current market metrics (price/book ratios and cyclically adjusted earnings multiples) have only been this extreme four other times in history:
Every single time was followed by a devastating correction.
Acadian Asset Management’s Owen Lamont created a framework to test if we’re really in a bubble. He calls it the Four Horsemen—and they’re all showing up.
| Horseman | What It Means | Are We There? |
|---|---|---|
| 1. Extreme Overvaluation | Stocks priced way above historical norms | Yes |
| 2. "Bubble Beliefs" | Investors know prices are too high but buy anyway, expecting them to go higher | Yes |
| 3. Surge in Equity Issuance | Companies rushing to sell stock/IPO while prices are high | Happening RIGHT NOW |
| 4. Flood of New Participants | Unsophisticated investors piling in (leveraged ETFs, "crapshooting") | Yes |
Important Callout: Dalio maps directly onto Horseman #3. He says: "There’s almost nothing easier to produce than stock. A company raises $50M, gets valued at $1B, and mints a paper billionaire—without a billion dollars ever changing hands."
This isn’t theoretical anymore. The calendar is packed with mega-IPOs:
| Company | Status | Target Valuation | Red Flags |
|---|---|---|---|
| SpaceX | Went public June 2026 | Largest IPO ever | Trading below IPO price; S&P projects negative free cash flow through 2029; Moody’s flags Musk’s voting control as governance risk |
| Anthropic | Confidentially filed, expected Oct 2026 | ~$1 trillion | |
| OpenAI | Filed separately, targeting 2027 (slipped from late 2026) | >$1 trillion | "Shifting market dynamics" cited for delay |
"Buy a unit of an AI company for $100. Borrow against that paper wealth. When the market turns and everyone needs cash at once, the price collapses to $25—but the loan still needs repaying."
His core distinction:
Wealth ≠ Money
"You see people getting wealthy but you can’t spend wealth. You have to sell wealth to get money—because you can only spend money."
When asked directly if he sees a bubble, Dalio didn’t hedge:
"Yeah. Yeah. Yeah. Classic signs that we’re in [one]."
He emphasizes:
Grantham adds the why: Markets are "constitutionally incapable of looking further than the present moment"—they extrapolate current conditions and "double-count prosperity" until the excitement itself becomes the risk.
This is huge: the most consistently bullish research shops are changing their tune.
| Firm | What They Said (Aug 3, 2026) | Translation |
|---|---|---|
| Goldman Sachs | "There does not appear to be a valuation bubble… there may be an earnings bubble in technology" | Stock prices might make sense if earnings materialize—but those earnings might be a mirage |
| Apollo (Torsten Slok) | "The 60/40 portfolio is broken" | The classic stocks/bonds mix hasn’t worked as predicted for 40 years |
| BCA Research (Peter Berezin) | AI trade is "primarily an earnings bubble rather than a valuation bubble" | Like pre-2008 banks: boom-bust cycle driven by imagined future profits |
| Company | Earnings | Stock Reaction | What It Signals |
|---|---|---|---|
| Microsoft | Strong | +18% | Capex credibility rewarded |
| Amazon | Strong | +10% | Capex credibility rewarded |
| Alphabet | Strong | -4% | Spending no longer rewarded just for existing |
| Meta | Strong | -10% | Bubble stage nearing "some kind of reckoning" |
Dalio doesn’t just see a market cycle—he sees an 80-year "Big Cycle" combining:
Dalio identifies two forces that historically burst bubbles:
| Force | How It Works | Current Status |
|---|---|---|
| Rising Interest Rates | Makes debt expensive to service | Aligns with Slok’s "higher for longer" warning |
| Surge in Stock Issuance | Companies rush to cash in on hype | Happening now (SpaceX, Anthropic, OpenAI) |
Dalio shared a conversation with a friend running an AI company who was raising hundreds of millions specifically because he expected a downturn—planning to use the cash to buy struggling competitors when the market turns.
Important Callout: Even the insiders are preparing for the crash.
Dalio’s biggest fear isn’t portfolio losses—it’s what happens socially and politically when the bubble bursts:
"When a bubble bursts, you have people at each other’s throats."
He cites the UK’s six prime ministers in seven years as a symptom: governments run out of money, voters turn on each other over how to raise it, and instability follows.
Grantham takes an even longer view, tying market excess to demographic collapse and resource scarcity.
In Dalio’s telling: The bursting of an AI bubble isn’t just a financial event—it’s the spark for the political and geopolitical conflict that historically accompanies the end of an 80-year cycle.
Not necessarily. Dalio says bubbles are a "degree thing," not a light switch. But do review your leverage, concentration in AI/tech, and whether you’re investing money you can’t afford to lose. Diversification and cash reserves matter more in bubble territory.
The classic 60% stocks / 40% bonds mix has been the default retirement strategy for 40 years. If it’s "broken" (stocks and bonds falling together, as in 2022), your retirement plan may need rethinking—more diversification, alternatives, or active management.
No. Dalio and Grantham aren’t saying AI is fake—they’re saying the financial speculation around it has detached from reality. The internet was real in 1999 too; that didn’t stop Pets.com from going to zero.
Understand the difference between wealth and money. Don’t borrow against paper gains. Keep dry powder (cash/short-term bonds). Avoid leverage. And remember: bubbles can stay irrational longer than you can stay solvent—but they always revert.
Final Thought: The smartest investors in history are screaming "CAUTION" in unison. You don’t have to panic—but you do have to pay attention. The cost of ignoring them could be far higher than the cost of preparing.