The safest the turkey has ever felt

Billund is a flat, unremarkable town in Jutland. In 1942 the workshop there burned to the ground for the second time, and the Danish carpenter who owned it, Ole Kirk Christiansen, rebuilt with wood he could barely afford, in a country under German occupation, making ducks and yo-yos for children whose parents had no money. Everything about that moment said the business would die. It didn't. Sixty years later, having survived a war, a currency collapse, and the arrival of the video game console, the company was posting its best numbers ever, and then very nearly went bankrupt in the space of about eighteen months. The Lego Story: How a Little Toy Sparked the World's Imagination is worth reading for the part most people skip, which is not the plastic brick but the near-death that arrived precisely when the record was longest and cleanest.

Taleb's line on the turkey is that the harm is in the future, not in the narrowly defined past. The turkey's data set improves every single day. A thousand days of being fed at the same hour is the strongest evidence available that day one thousand and one will look the same, and the evidence is not wrong, it is simply pointing the wrong direction.

Long track records feel like proof. They are mostly a description of what has not happened yet. The fire that destroyed the workshop was survivable because the business was small and the owner was young and nobody had built anything on top of the assumption that it would last. The crisis that nearly ended the company came when the assumption was load-bearing.

Notice which of those two you are living inside.

Ask a bomber pilot in a bear market

Somewhere today a person is filling in a form with a pen. On a scale of one to five, how would you feel if your portfolio fell twenty percent? The investment writer Robert Hagstrom relays Pruitt's observation that investors respond to markets the way Walter Mitty responded to life. In a rising market they answer as a fearless bomber pilot. In a falling one they answer as a henpecked husband. Same person, same form, two entirely different animals holding the pen.

The risk-tolerance questionnaire is astrology with a compliance department attached.

What interests me is not that the answers change, but that both answers are honest. The measurement is real. It is the ruler that keeps changing length. I wrote about this in Diligence and Allocating Attention Across a Living Surface — Spain measures its border with Portugal at 987 kilometres and Portugal measures the same border at 1,214, and neither is wrong, because the answer depends entirely on how fine your instrument is. Coarse ruler, short border. Fine ruler, long border.

Your tolerance for loss works the same way. In a calm market you measure it with a coarse instrument: a number on a page, an abstraction, twenty percent of a figure you check monthly. In a drawdown the instrument gets very fine indeed. You measure it in the hour you wake at three in the morning, in the conversation you avoid having with your spouse, in the position you sell not because the thesis broke but because you wanted the noise to stop.

The only useful risk tolerance is the one measured with the fine instrument. Which means you cannot know it in advance, only recall it afterwards, which is why the second time through a crash is different from the first.

The governor in your skull

The Comrades Marathon runs 90 kilometres between Durban and Pietermaritzburg, up through the hills of KwaZulu-Natal, and it has been run since 1921. Thousands finish it every year. Almost nobody dies doing it. That fact bothered the South African physiologist Tim Noakes enough that he built a theory around it: something in the brain applies the brakes long before the muscles actually fail. The body is not the limit. The governor is.

Gio Valiante, a performance psychologist who has spent his career with elite athletes and traders, puts the conclusion bluntly. Underperformance is built into the human condition so that we can stay alive. The brain's job was never excellence. It was keeping a mammal fed and unbitten long enough to reproduce. Put a single-celled organism on a plate that is hot on one side and cold on the other, and it moves toward comfort without deliberating. So do you. The deliberation you experience is largely decoration on a decision already taken by something older than your opinions.

In markets the governor does not show up as panic. Panic is loud and easy to spot. It shows up as reasonableness. The position sized so small that being right about it changes nothing. The extra name added to the portfolio not because it is better but because holding fourteen feels safer than holding nine. The years of research that produce a conclusion you then decline to act on with any force. All of it feels like prudence. Most of it is a nervous system protecting you from the discomfort of a concentrated bet you would have to look at every day.

Valiante quotes William James, who concluded that his first act of free will would be to believe in free will. Not a slogan. A procedure. You cannot remove the governor, and you would be an idiot to try, but you can notice the exact moment it engages, and you can decide, occasionally, deliberately, in full knowledge that it will hurt, to keep going another hundred metres.

Most people never find out where their limit actually sits. They stop at the place the brakes were applied and call it the edge.

My Ledger — notes on investing, books, and things I'm still figuring out. The Library is where I keep the books that shaped how I think. The Journal is where I work through ideas in public.

Mandelbrot — the private toolbox behind the thinking.

Hit reply if something here sparked a thought. I read every response and always write back.