57 / Water
Turn off the tap while brushing
Water avoided equals tap flow multiplied by the time it stays off.
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UNIVERSALIZABLE.COM1785 — 2026
— Immanuel Kant, Groundwork of the Metaphysics of Morals, 1785Act only according to that maxim through which you can at the same time will that it become a universal law.
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Handle nur nach derjenigen Maxime, durch die du zugleich wollen kannst, daß sie ein allgemeines Gesetz werde.
— Immanuel Kant, Grundlegung zur Metaphysik der Sitten (1785)A question from 1785. A possibility for today.
Explore the possibilities ↓EVERYDAY CHOICES · SHARED POSSIBILITIES
Start with something familiar.
A journey, a meal, a light left on. Find a change that makes sense in your life, then explore what it could mean when others join in.
Explore all 60 actions01 / The collection
All 60 actions A few places to begin
10 / Things we use
Bring a reusable coffee cup
A cup used repeatedly can displace disposable cups.
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46 / Food
Plan a meal around what you have
Food eaten rather than discarded can avoid waste and unnecessary replacement purchases.
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14 / At home
Let a load of laundry air-dry
Replacing a dryer cycle saves the electricity it would have used.
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What if the rule behind your choice became everyone’s rule?
Universalizable puts Kant’s question into numbers. Pick an everyday action and see what it adds up to: for you, for your friends, for everyone.
The question behind the name