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No. 347 · Fixing problems · Military and War

Quarantine

Isolate what might be harmful long enough to learn whether it really is.

Quarantine is the deliberate isolation of people, places or resources that might carry a threat, long enough to see whether the danger is real. The word comes from Venice's forty days, after Ragusa pioneered a thirty-day rule in 1377.

Use it for anything contagious: pilot new tools with one team, put big purchases on a thirty-day list, and save angry emails as drafts overnight. Keep quarantines clear, time-limited and proportionate.

In the Almanac

“Ragusa’s thirty days”, 1377 · “The NBA bubble”, 2020

Both stories in full, three ways to use it and where it misleads.

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Quarantine

Questions

What is Quarantine?

Quarantine is the deliberate isolation of people, places or resources that might carry a threat, long enough to see whether the danger is real. The word comes from Venice's forty days, after Ragusa pioneered a thirty-day rule in 1377.

How do you use Quarantine?

Use it for anything contagious: pilot new tools with one team, put big purchases on a thirty-day list, and save angry emails as drafts overnight. Keep quarantines clear, time-limited and proportionate.

When does Quarantine matter?

Quarantine is one of the 40 mental models for fixing problems, the situations where you ask: Why does this keep going wrong, and how do I fix it for good? Within that, it belongs to “How problems spread”, alongside Broken Windows Theory, Chain Reaction and Containment.

What is an example of Quarantine?

Two stories show it at work: Ragusa’s thirty days (1377) and The NBA bubble (2020). Both are told in full in The Mental Models Daily Almanac, which has two stories for each of its 365 models.

Which mental models are related to Quarantine?

A/B Testing, De-Risking and Margin of Safety. Quarantine itself comes from military and war.