Entropy
Entropy is a measure of disorder, and physics says it always increases in a closed system. As a mental model, it captures the universal tendency for things — rooms, organisations, relationships — to drift toward disorder unless energy is continually spent to maintain order.
How it works
Treat order as costly and temporary. Anything organised — a tidy house, a coherent strategy, a healthy team — requires ongoing energy input just to stay as it is, because the natural drift is toward decay, mess, and disorganisation.
Most things don't fail from a dramatic event — they fail from the slow, automatic accumulation of neglect.
How to use it
- Understanding why maintenance, not just creation, is required to keep anything good alive.
- Anticipating that systems, codebases, and organisations rot without continuous upkeep.
- Budgeting energy for "holding the line," not only for building new things.
Worked example
A clean kitchen doesn’t stay clean — left alone, it gradually fills with clutter and grime. Keeping it ordered takes constant energy (cleaning); the disorder is free and automatic. The same drift afflicts every organised system.
Where it fails
The physics applies strictly to closed systems; life and organisations are open systems that import energy to create local order. Over-literal use ("everything inevitably decays") ignores that sustained effort genuinely can maintain and even grow order.
- The metaphor gives no rates: it says maintenance is required but not how much, so it cannot arbitrate between over- and under-investing in upkeep.
- Applied to organisations, 'disorder' is an observer's judgment rather than a measurable quantity, so the analogy can dress opinion as physics.
- It frames all change as decay, hiding that some drift — in habits, markets, teams — is adaptation worth keeping.
The counter-model: Compounding — Entropy says order erodes by default; compounding shows small, consistent reinvestment can grow order faster than it decays.
How to apply it, step by step
- List what you rely on that no one currently maintains — systems, relationships, skills, documentation.
- Accept that each degrades by default; the absence of effort is itself a decision to let it decay.
- Schedule regular maintenance energy for the ones that matter most.
- Deliberately let the rest run down — maintenance budgets are finite, so choose your decay.
The deeper point
It reframes maintenance as heroic, not boring: keeping something good in working order is a constant fight against the universe’s default. Most things don’t fail from a dramatic event — they fail from the slow, free, automatic accumulation of neglect.
Frequently asked
- What is entropy as a mental model?
- It’s the principle that things naturally drift toward disorder unless energy is spent to maintain order. Borrowed from physics, it captures why rooms, organisations, and systems decay without continuous upkeep.
- What is an example of entropy in everyday life?
- A tidy room becomes messy on its own but never tidies itself — order requires energy (cleaning), while disorder is automatic. The same one-way drift toward mess affects teams, code, and relationships.
- Does entropy mean everything inevitably decays?
- In a closed system, yes. But living things and organisations are open systems that import energy to create and maintain local order. The lesson is that order is costly and temporary, not that decay can never be resisted.
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The books behind better thinking
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- Thinking, Fast and Slow — Daniel Kahneman
- The Art of Thinking Clearly — Rolf Dobelli
- The Great Mental Models, Volume 1 — Shane Parrish
- Poor Charlie’s Almanack — Charlie Munger
- Super Thinking — Gabriel Weinberg & Lauren McCann
- Seeking Wisdom — Peter Bevelin
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Cite this page
ReadGlobe. (2026). Entropy. https://readglobe.com/model/entropy/
"Entropy." ReadGlobe, 29 May 2026, readglobe.com/model/entropy/.
Primary source: Wikipedia
Editorial synthesis © ReadGlobe 2026, drawing on the mental-models tradition (Charlie Munger, Farnam Street) and the primary sources for each model. · Last reviewed 2026-05-29.