The Shape of a Good Surprise

There's a simple thought experiment: picking up pennies in front of a steamroller. For a while, the strategy delivers a steady, predictable, and satisfying return. The problem isn't the pennies; it's the steamroller. The catastrophe, when it arrives, is total.

This is a concave arrangement. You accept small, limited gains while exposing yourself to catastrophic, unbounded loss. It hates surprises, volatility, and error.

The opposite posture is convex. More upside from being right than downside from being wrong. A favorable asymmetry where you are positioned to benefit from what you don't—and can't—know.

This isn't just about finance. It’s a shape that repeats everywhere.

A library is a convex institution. The cost of acquiring another book is small and known. The potential upside of the one idea in the one book that changes your mind is nearly infinite.

A cocktail party is a convex bet. The downside is a wasted evening. The upside is a new friend, a new job, a new collaborator, a new way of seeing the world.

The venture capitalist's portfolio, the research scientist's series of small experiments, the curious wanderer exploring a city with no map—all are searches for a convex payoff. They are structured to be pleasantly surprised. Most bets yield nothing, but one success pays for all the failures and then some.

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A practical heuristic for engineering this asymmetry into your own life is the barbell strategy.

Place the vast majority of your resources—say, 80-90%—in the safest, most robust assets possible. The cash under the mattress. The established career. The proven health regimen.

Then, deploy the remaining 10-20% in a multitude of small, speculative, high-risk, high-reward bets. The "crazy" side projects. The angel investments. The experimental new habits.

What you're avoiding is the "middle"—the medium-risk, medium-return strategies that are often exposed to hidden, concave risks without the commensurate explosive upside. The barbell doesn't try to optimize for a predictable future; it prepares to benefit from an unpredictable one.

It’s a strategy for loving volatility.

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Convexity is the essence of optionality. An option is the right, but not the obligation, to do something.

This separation of right from obligation is the entire game. You pay a small, fixed price to gain exposure to unlimited upside. The more the world shakes, the more chaotic and unpredictable things become, the more valuable your option becomes.

Someone with options doesn't need to predict the future. They just need to know whether the payoff structure is favorable. Is there more to gain than to lose from a surprise?

This is why "efficiency" is so often the enemy of robustness. A hyper-efficient, just-in-time supply chain is a concave system. It generates predictable, small gains from its optimization, but a single unexpected shock—a storm, a pandemic, a blocked canal—can bankrupt the entire enterprise. It has traded resilience for performance.

The most robust path is often not to add, but to subtract. Don't ask, "What can I do to succeed?" First, ask, "What can I remove that might make me fail?" This is via negativa. Ruthlessly eliminate the concave arrangements in your life—the things that expose you to the possibility of ruin.

Ruin is a state you cannot come back from. Avoiding it is the first and only unbreakable rule. Once you’ve ensured your survival, you can spend the rest of your time arranging your affairs to catch the winds of luck and randomness. Not by predicting the storm, but by building a better sail.