TThe Diary of a CEO
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25 June 2026

Billionaire's WARNING: I'm SELLING. The Crash Is Already Here!

4Frameworks
15Insights

Frameworks in this episode

Insights & moments

The myth-busts, hot takes, explainers, and tools worth keeping.

Hot Take· 5

Hot Take36:30

Grantham Says AI Turns Seven Monopolies Into One Brutal Contest

Grantham contrasts the major technology companies' historically distinct, profitable markets with their present competition in AI. He argues that simultaneous heavy capital spending and borrowing could erode the economics those firms enjoyed, although he does not predict which company will win.

  • The companies previously dominated different categories such as search, chips, and smartphones
  • Grantham says they are now spending heavily in the same AI arena
  • He describes the contest as one in which participants expect winner-take-most outcomes
  • Large capital expenditure can reduce returns even when the technology succeeds
  • He suggests opting out may be rational for one or two firms
  • The episode does not provide company-level valuation or cash-flow analysis

They're all girding for battle in the same marketplace, AI.

Jeremy Grantham · 37:30

It looks like seven people in the ring.

Jeremy Grantham · 38:00
#mag seven#ai competition#capital expenditure#strategy
Hot Take52:30

The Episode's Warning About Extreme Wealth Inequality

Grantham argues that widening inequality weakens satisfaction and social cohesion, contrasting recent decades with a period when income gains were more broadly shared. Bartlett then cites research claiming extreme inequality historically ends through collapse, war, or revolution; that three-part inevitability claim is the host's summary and is not substantiated with named studies in the transcript.

  • Grantham identifies inequality as a major economic problem
  • He says typical US hourly earnings have barely improved after inflation since the mid-1970s
  • The host supplies several wealth-distribution statistics without source details in the episode
  • Bartlett presents a three-trigger historical reset claim that should not be treated as established fact
  • Grantham favors gradual tax and distribution changes over violent correction
  • His proposed direction is for lower-income groups to gain slightly faster than average

I think that's the biggest economic problem.

Jeremy Grantham · 53:00

It needs a government that is prepared

Jeremy Grantham · 56:30
#inequality#wealth#social cohesion#taxation
Hot Take58:30

Grantham's Blunt Answer to a 33-Year-Old Who Wants to Get Rich

Asked to optimize only for becoming rich, Grantham says he would enter AI, learn more than competitors, join a leading firm, take substantial risk, and work hard. He also warns that this narrow objective could contribute to harmful AI development, so the answer is explicitly about wealth maximization rather than a general life recommendation.

  • Grantham chooses a large incoming technology wave rather than a defensive career
  • He emphasizes deep knowledge and proximity to a leading organization
  • He recommends risk-taking and questioning conventional rules
  • He does not discuss personal downside, ethics, family obligations, or risk capacity in detail
  • His answer conflicts with his more defensive advice for invested savings because the objectives differ

Try and know more about everything in that area than the next guy.

Jeremy Grantham · 59:00

Take lots of risk. Don't be conservative.

Jeremy Grantham · 59:30
#career#ai#wealth#risk taking
Hot Take1:02:30

Why Grantham Rejects Crypto as an Investment

Grantham says he has never owned crypto and would not recommend it. He argues that its volatility undermines the store-of-value case, its everyday use as money is limited, and its strongest function is speculation; his broader assertion that it facilitates only criminal transfers is an unsupported opinion in the episode.

  • Grantham owns no crypto and says he never plans to
  • He cites large price swings against the store-of-value claim
  • He says it is inconvenient as an everyday medium of exchange
  • He accepts that crypto functions effectively as a speculative asset
  • His crime-only characterization is overstated and not evidenced in the transcript
  • His prediction that Bitcoin eventually reaches zero is a forecast

It's not stable. It's volatile as hell.

Jeremy Grantham · 1:03:30

It's a means of speculating beautifully.

Jeremy Grantham · 1:03:30
#crypto#bitcoin#speculation#volatility
Hot Take1:31:00

Grantham's Case for Treating Family Formation as a Public Good

Grantham argues that a stable population of healthy, well-educated children should be treated as shared infrastructure alongside clean air, water, and fertile soil. He uses the replacement-rate figure of 2.1 children per couple for rich societies and calls for more family-friendly social and economic norms, while acknowledging that existing policies have not produced a durable fertility increase.

  • Grantham presents 2.1 children per couple as an approximate replacement rate
  • He calls children part of the commons rather than solely a private responsibility
  • He links low birth rates to economic, social, and claimed toxic exposures
  • He argues that childcare and family support require whole-society participation
  • He says many international policy attempts have failed to create a permanent increase
  • The model is a political and ethical proposal, not a settled policy prescription

2.1 is the number of children it takes for a rich society to have a steady population.

Jeremy Grantham · 1:32:00

All of them have to be treated as group responsibility.

Jeremy Grantham · 1:33:00
#fertility rate#family policy#public goods#demographics

Explainer· 6

Explainer09:30

How Grantham Thinks a Stock Crash Reaches Jobs and Spending

Grantham predicts that the most expensive, fast-rising shares would suffer the largest losses in a reversal. He says falling wealth can reduce spending and pressure employers, while acknowledging that historical recessions had causes beyond market crashes.

  • Grantham says high-flying AI and growth stocks would be most exposed
  • He presents a 70% decline as plausible, not certain
  • He says layoffs can follow when highly valued companies come under pressure
  • He describes a reverse wealth effect in which people feel poorer and spend less
  • He notes that factors beyond the market contributed to the Great Depression

The high flyers will probably come down a lot.

Jeremy Grantham · 09:30

People feel a little bit poorer, they spend a little less.

Jeremy Grantham · 12:00
#market crash#recession#wealth effect#jobs
Explainer29:00

The Tension Between Benevolent AI and Competitive Pressure

Grantham argues that advanced AI should be made reliably benevolent before development accelerates further. Bartlett counters that users may leave systems they experience as judgmental, creating pressure for companies to weaken restrictions; both present this as a risk argument rather than a demonstrated future outcome.

  • Grantham says AI experts disagree sharply about benefits and existential risks
  • He treats reliable benevolence as a possible safety requirement
  • Bartlett says definitions of good and harmful behavior are contested
  • Bartlett predicts competition could punish systems perceived as too restrictive
  • Grantham argues that failure to solve alignment could eventually produce severe harm
  • The discussion offers no tested method for encoding benevolence

You should make sure you can do that before you push ahead.

Jeremy Grantham · 30:30

Any model that does that will be losing model

Steven Bartlett · 34:00
#ai safety#alignment#competition#benevolence
Explainer35:00

The Paperclip Thought Experiment in Plain English

Grantham explains the paperclip maximizer as a warning about giving a powerful machine a literal, open-ended goal. Bartlett summarizes the lesson as an unintended-consequences problem: a harmless objective can become catastrophic if its limits and effects are not specified.

  • The hypothetical system receives a simple goal to maximize paperclips
  • The instruction does not protect other human values or resources
  • Greater capability lets the system pursue the goal at expanding scale
  • The example illustrates specification failure rather than a forecast that AI will literally make paperclips
  • Bartlett argues that longer time horizons create more opportunities for unforeseen harm

A sloppily open-ended bad definition.

Jeremy Grantham · 35:00

The unintended consequences of a simple good-meaning instruction can sometimes cause catastrophe

Steven Bartlett · 35:30
#ai safety#paperclip maximizer#unintended consequences
Explainer1:04:00

Why Grantham Questions Property at Today's Prices

Grantham argues that housing can be a poor investment when prices are already far above household incomes. He adds that declining family formation and population in richer countries could weaken future demand, though the episode does not provide enough localized evidence to turn that thesis into a universal property forecast.

  • He says UK house prices rose from about 3.4 times family income in 1994 to over 10 times in some places
  • Even a 30% fall would leave his cited affordability ratio historically high
  • High prices also raise rents and squeeze potential buyers
  • He rejects the idea that unaffordability automatically guarantees further gains
  • He expects fewer young households to reduce demand in some countries
  • Property outcomes remain local and depend on supply, credit, migration, and policy not fully discussed

If people can't afford it, there's no one bidding.

Jeremy Grantham · 1:04:30

Young family formations are already declining in many of the richer countries.

Jeremy Grantham · 1:04:30
#housing#property#affordability#demographics
Explainer1:09:00

What Grantham Claims About Falling Sperm Counts

Grantham cites work by Shanna Swan and Hagai Levine to argue that sperm counts have fallen sharply and that the decline is accelerating. The episode supplies dramatic figures and a 2045 projection but not study titles, methods, uncertainty ranges, or the distinction between sperm count and sterility, so these claims should be checked with reproductive-health evidence and clinicians rather than used for self-diagnosis.

  • Grantham says reported average sperm counts have nearly halved since early academic measurements
  • He claims a current decline rate of about 2.5% per year
  • He presents historical and present concentration estimates without methodological detail
  • The host says Swan projects a median count of zero by 2045 if the trend continues
  • A projection based on continued trend is not a certainty
  • The discussion does not establish an individual's fertility from a population average

We got to study the data

Jeremy Grantham · 1:11:00

If the current rate of decline continues unchecked

Steven Bartlett · 1:13:30
#fertility#sperm count#reproductive health#research claims
Explainer1:16:30

The Small Fertility Studies Grantham Uses to Question Pesticides

Grantham describes two small observational studies from a Harvard and Massachusetts General fertility clinic that relied on self-reported diets. He says lower consumption of high-pesticide produce was associated with higher sperm counts in men and more live births in women, but the episode does not provide citations, adjustment details, or evidence that pesticides caused the differences.

  • Grantham describes a study of 180 men attending a fertility clinic
  • He reports roughly double the sperm count between the lowest- and highest-exposure groups
  • He describes a later study in women and reports 68% versus 38% live-birth rates
  • Diet was self-reported and the participants were fertility-clinic patients
  • Association in small observational studies does not establish causation
  • Listeners should not alter fertility treatment or nutrition from the episode alone

They're very small

Jeremy Grantham · 1:16:30

This was only based on what they ate.

Jeremy Grantham · 1:18:00
#pesticides#fertility#observational study#nutrition

Story· 1

Story45:00

How Grantham Says Tesla Turned Valuation Into Factories

Grantham says Tesla's high share price enabled it to sell stock, fund factories, and turn investor confidence into operational capacity. He calls the process self-fulfilling, then argues that SpaceX would need similarly favorable confidence and market timing to meet its much larger promises; this is his interpretation, not an established verdict on either company.

  • Grantham says Tesla's valuation exceeded what he considered fundamentally justified
  • Selling highly valued shares supplied capital for new factories
  • Continued investor confidence prevented fundraising from crushing the share price in his account
  • Operational expansion then helped validate part of the earlier confidence
  • He doubts SpaceX will repeat the cycle at its present scale
  • Bartlett presents real SpaceX and Tesla achievements as counterevidence to dismissing ambitious claims

It became a self-fulfilling prophecy.

Jeremy Grantham · 46:30

It doesn't really count until you've cashed it in.

Jeremy Grantham · 45:00
#tesla#spacex#elon musk#financing

Q&A· 1

Q&A1:27:30

Grantham's Pregnancy Advice—and Why It Needs Clinical Review

Grantham tells pregnant women to avoid cosmetics for nine months and prioritize organic versions of selected produce, claiming this could remove a large share of harm. The transcript does not establish that estimate, define which products or exposures matter, or weigh nutritional, financial, and clinical trade-offs, so the recommendation should be treated as his claim and discussed with qualified prenatal clinicians.

  • Grantham prioritizes pregnancy because he believes fetal development is especially vulnerable
  • He recommends eliminating cosmetics during pregnancy
  • He suggests buying organic versions of produce he calls the dirty dozen
  • He later names gas stoves, black plastics, and nonstick pans as exposures to review gradually
  • His claim that two changes could remove half the trouble is unsupported in the episode
  • Pregnant listeners should not replace prenatal guidance or adequate nutrition with podcast advice

Pregnant women are much more important than anybody else in this field.

Jeremy Grantham · 1:27:30

You do one thing after another.

Jeremy Grantham · 1:28:00
#pregnancy#prenatal health#cosmetics#organic food

Tool· 1

Tool1:26:00

Product-Scanning Apps the Host Suggests for Ingredient Checks

Bartlett recommends Yuka, EWG's Healthy Living, Think Dirty, and Clearya as tools for checking product ingredients, while saying he is not affiliated with them. His surrounding claims about plastics, pesticides, cosmetics, sperm counts, cancer, and neurodevelopment are presented without source details in the transcript, and an app score is not a medical diagnosis or proof of harm.

  • Yuka is described as a barcode scanner that gives products a score
  • EWG's Healthy Living covers food, cleaning products, and cosmetics
  • Think Dirty focuses on cosmetics, shampoo, and skin care
  • Clearya is described as a browser aid for online shopping
  • The host also suggests using AI to ask questions about photographed products
  • Ingredient ratings should be checked against authoritative regulatory and medical guidance

I'm not affiliated with any of them

Steven Bartlett · 1:26:00

You can just scan the barcode

Steven Bartlett · 1:26:00
#product scanning#ingredients#consumer apps#toxicity claims

Takeaway· 1

Takeaway26:00

Why Grantham Tells Capital-Dependent Founders to Raise Early

Bartlett describes an AI founder planning to raise capital before a possible downturn closes funding markets. Grantham approves the logic and advises founders to lock up money and introduce conservatism where possible, while the timing and severity of any downturn remain forecasts.

  • A downturn can make external capital harder to obtain
  • Cash raised in favorable conditions can extend a company's runway
  • Conservatism can include reducing dependence on optimistic assumptions
  • The strategy has dilution and capital-efficiency trade-offs not explored in the episode
  • Grantham cannot specify whether the predicted problem is weeks or years away

If you can lock up money, I would.

Jeremy Grantham · 27:00

Brace yourself for impending problems.

Jeremy Grantham · 27:00
#founders#fundraising#runway#recession