The Belfry Problem

I

It is a fairytale town, and nobody in it thinks so

The film this borrows its shape from is about exactly one disagreement. Two men are put in a medieval Flemish town to wait. Ken walks it, climbs the belfry, stands in front of the Bosch panel, and finds the place extraordinary. Ray sees a canal, some bricks, and an eternity of nothing to do. Neither is lying. They are standing in the same streets with different amounts of the town available to them.

Frontier has the same disagreement in it, and it has been having it in writing for four days. On one side there is an author who can see the whole coast: a nine-good economy with a metal ladder, forty catalogue kinds a settlement can vote itself, a single-transferable-vote ballot with every transfer recorded. On the other there are fifteen people who can see a woodpile.

The previous notice ran the two of them against each other as a controlled trial and got the attribution wrong twice in one morning. This one asks the question that was actually underneath it: what, precisely, does a settler get to look at?

II

Fifteen objects

When the game hands a settler over, it writes down everything that settler can see. It is a short document. The nearest tree, the nearest rock, the nearest seam and the nearest berry bush, each within thirty paces — four things. Up to six people within forty-two paces. The five nearest buildings.

The settlement's own logic — the four hundred lines the settlers fall back on when nobody is thinking for them — reads the whole store, every building on the coast, the complete build-cost table and the entire recipe graph, on every decision, for free. It is not cleverer. It is standing on the tower.

III

Three hundred and twenty-seven houses

Here is what four days of this produced. Every building finished by anybody, in any valley, across the whole record:

Three hundred and twenty-seven houses and one furnace. Seventy-six per cent of everything ever built on this coast is the same building.

And it is not a preference, or a failure of ambition, or a language model being dim. It is the only building on that list whose reason is inside forty-two paces. A settler standing in the settlement can see a person with nowhere to sleep. They cannot see that four boards would start a metal ladder that ends in a saw, a pick, a struck coin and a hall that lets a sixteenth person land, because none of that is anywhere in the fifteen objects they were handed. The house is the one decision this valley has ever been equipped to make.

IV

The tower they kept asking for

Now the part that would be too neat to write if it were not on the record.

This game already contains the cure for its own short sight. There is a boon called sightlines, granted by a wish the catalogue files under lookout, and what it does is widen how far a settler will look before they decide where to work — from thirty-four paces to forty-eight. It is a belfry. Climb it and you can see further.

The settlers asked for it twenty-nine times, in eighteen different wordings, and the plainest of them is this:

Somewhere high with a bench, to see the valley whole and know what is out past it.

Four towers, in four hundred and thirty-one buildings. Under one per cent. The reason is the ladder again: a tower wants eight dressed blocks, blocks want a masons' yard, and three masons' yards have ever been built on this coast — of which, in the valley this notice was written in, exactly none had ever dressed a single stone.

The thing that would have let them see the problem was on the far side of the problem. A settler cannot see why to build the tower without the tower. In the film, Ray will not climb the belfry because he cannot see what would be worth the climb, and the joke is that the answer is at the top of the stairs.

V

Harry's principle

The film's third man holds one rule absolutely and follows it, in the end, straight off the bottom of the tower, on a misreading of a fact that a moment's looking would have corrected. He is not stupid either. He is consistent.

This project has been Harry all week. The rule is: a settlement may only have what it has voted for, which is a good rule and the whole point of the game. Applied without looking, it produced a valley that had voted a kiln into existence and could not burn anything in it, because burning wants a furnace and the furnace wanted four boards and the boards wanted a mill and the mill wanted iron that only the furnace could make. Every step of that was correct. The result was a shed with a name on it.

Consistency is what a rule is for, and it is also the exact failure mode of a rule that cannot see the thing it is being consistent about. That is the same sentence as the one about the settler and the woodpile, which is why this notice has one argument in it and not two.

VI

What was handed down

The trial's own closing paragraph said the fix would be to give the model a wider view rather than take the model away. That was written at 08:20 and done by 08:40, which is the one thing this shelf can say for itself.

What a settler is shown now includes the settlement, in words rather than in nouns. Not ["kiln","masons","joiner"] — which is what it read for the whole of this project's life, and which is how a model came to be told a valley had a kiln when it had a shed — but:

Three fields. Each of them was computable from the object it sits in, on every one of the 6,848 decisions this valley has ever paid a graphics card for, and none of them was in it. Within four hundred ticks of the change the settlement had lit a kiln and drawn two bars of iron — the first metal anybody has ever made here.

Which does not prove the change did it. Four deadlocks were cleared the same morning and this valley is one valley. It is written down so that the next person to run the experiment has something to disagree with.