In 1637, in the Dutch Republic, a single tulip bulb could cost more than a skilled craftsman earned in a decade.
This was not madness in the way we usually imagine madness. The people buying tulips were not fools. There was a real story: tulips were genuinely beautiful, genuinely fashionable, genuinely scarce in their rarest varieties, and prices had genuinely been rising for years. Everyone buying could point to everyone else buying as proof they were right. Then, almost overnight, the story broke, and a bulb that cost a fortune on Monday was nearly worthless by Friday.
Nearly four hundred years later, the surface details keep changing, the railways, the radio companies, the dotcoms, the houses, the various crypto cycles, but the script underneath stays almost identical. Learning to recognise that script is one of the most protective things an investor can do.
Stories move markets more than numbers do
The economist Robert Shiller, who won a Nobel Prize partly for this work, gave the idea a name: narrative economics. His argument is that markets are not driven purely by cold fundamentals. They are driven, often more powerfully, by stories that spread from person to person like a contagion.
A story takes hold: this technology changes everything, this kind of asset only goes up, the old rules no longer apply. The story spreads. People act on it. Their buying pushes prices up. The rising prices appear to confirm the story, which helps it spread further, which pushes prices higher still. For a while, the story is self-fulfilling, and that is precisely what makes it so convincing from the inside.
This is the link to the herd behaviour from earlier in the series. The herd does not stampede over nothing. It stampedes over a story.
The anatomy every bubble shares
Strip away the specifics and almost every bubble has the same four parts.
- A plausible story. Crucially, it is usually built on something genuinely real. Tulips really were fashionable. The internet really did change the world. Houses really are valuable. The kernel of truth is what makes the enthusiasm feel reasonable rather than ridiculous, and it is what disarms the sceptics.
- Rising prices that seem to prove it. The climb becomes its own evidence. “It keeps going up, so the story must be right.” Price action gets mistaken for confirmation.
- New-era thinking. The belief that the normal rules of value no longer apply, because something fundamental has changed. Old measures of what a thing is worth get waved away as relics from before the new era.
- The four most expensive words in finance: “this time is different.” Whenever someone points to history and the past pattern of busts, the answer is that history does not apply here, for reasons that always sound specific and persuasive in the moment.
When you notice those four ingredients gathering, especially the fourth, you are not necessarily looking at a bubble. But you are looking at the exact conditions in which bubbles grow.
Why you cannot just spot it and step off
The obvious response is: fine, I will simply recognise the bubble and avoid it. It is much harder than it sounds, for a reason worth sitting with.
Inside a bubble, every signal that later looks like a flashing red warning instead reads as confirmation. Prices are rising, which feels like proof. Smart, respected people are participating, which feels like social proof. The story is genuinely plausible, so doubt feels like missing the point rather than wisdom. And anyone who sold early looks foolish for months or years before being proven right, which is its own punishment for caution.
Two biases thicken the fog:
- Recency bias makes us assume the recent trend just continues. Prices went up lately, so up feels like the natural direction of the world.
- Availability bias makes vivid, often-repeated stories feel more likely than they are. When every conversation and feed is full of people who got rich, getting rich starts to feel like the normal outcome rather than the rare one.
Together they make the inside of a bubble feel less like a bubble and more like simply being early to something obvious. That is why bubbles are clear in hindsight and murky in foresight.
Staying grounded without predicting the top
So the goal is not to become someone who calls the top, because almost nobody reliably can, and trying tends to cause its own mistakes. The goal is to stay grounded enough that no single story can take you down.
- Keep position sizes sane. No story, however convincing, should be allowed to grow into a bet that ruins you if it breaks. This is exactly the discipline that the satellite portion of a portfolio is meant to enforce: speculative, story-driven holdings are sized so that being wrong is survivable.
- Stay diversified. Diversification is, in part, protection against being completely right about the wrong story. If no single holding can sink you, no single broken narrative can either.
- Treat “this time is different” as a warning, not an invitation. When a story requires you to abandon the basics, ignore valuation, concentrate heavily, or borrow to join in, the story itself is the risk. The need to wave away history is the tell.
- Separate the truth in the story from the price. Often the underlying story is partly true. The internet did change everything. That truth still says nothing about whether today’s price is sensible. A great technology and a terrible price routinely coexist.
What you can do
- Learn the four-part script. Plausible story, rising prices, new-era thinking, “this time is different.” Once you can name the parts, you can spot the conditions even when you cannot call the timing.
- Watch for the warning phrase. Any time you hear, or catch yourself thinking, “this time is different,” slow down. It is the single most reliable signal that a narrative has outrun the numbers.
- Size for being wrong. Decide in advance how much of any story-driven bet you could lose entirely without it mattering, and never exceed it. Survival first.
- Hold the truth and the price apart. Ask the two questions separately: is the story true, and is the price sensible? The answers are often yes and no, and the second one is the one that protects your money.
Narrative economics is about the stories that move whole markets, the biggest, most external force of all. The next bias turns all the way inward, to the quietest stories of them all: the unspoken beliefs about money you absorbed in childhood and have been running on ever since, usually without knowing it. Those are money scripts, and they are where we go next.