Occam's & Hanlon's Razors

Simplify your assumptions with mental razors.


It’s been a while — I apologize.

Before jumping in I wanted to share something with you.

Musings & Perspectives was briefly (for 2 days) on a billboard on the west side highway in New York City.

Big shout-out to Matei for this (it was a birthday gift). Oh, and kudos to Kyle and Rachel from Morning Brew for hosting spectacular IRL events to connect new friends.

If you’re keen to learn more about billboard advertising, check out his Techstars-backed venture, TPS engage.

Also – Matei writes a very clever daily newsletter on practical applications of the concept Lateral Thinking. I read it every day.

As a continuation of my series on heuristics (mental rules of thumb), I’ll be covering Occam’s Razor and Hanlon’s Razor.

To refresh your memory — here are the previous mental models I covered:


What are razors?

Mental razors, heuristics, models — they’re all conceptually similar. The intention is to use a simple framework to guide decision-making and intelligent cognition.

In this case, it’s called a razor as it’s supposed to ‘shave away’ unnecessary assumptions, unlikely explanations, and ultimately — minimize noise.

Occam’s and Hanlon’s Razors are two frameworks that you can use for

Occam’s Razor

William of Occam was an English theologian, logician, and Franciscan friar. He once wrote: “Plurality must never be posited without necessity”.

In layman’s terms, the razor implies:

The easiest explanation tends to be the right one.

When you have two competing theories that form the same prediction, the simpler one is often better.

“We may assume the superiority, other things being equal, of the demonstration which derives from fewer postulates or hypotheses.”

— Aristotle

Why? Because simpler (and fewer) assumptions are more likely to be correct than complex ones.

We should avoid looking for excessively complex solutions to a problem, and focus on what works given the circumstances.


  • Doctors seek the fewest possible causes to explain the symptoms of their patients and give preference to the most likely causes.

  • The cause of a flat tire is more likely from a nail vs. someone intentionally slashing your tire.

  • Your romantic partner doesn’t reply to your text message for hours. It’s more likely a dead phone battery vs. them being secretly mad at you.

Hanlon’s Razor

Inspired by Occam’s razor, Robert J. Hanlon coined ‘Hanlon’s Razor’, which can be interpreted:

Never attribute to malice that which can be adequately explained by stupidity.

It’s better to assume that bad things happen because of absentmindedness, rather than bad intentions.

Hanlon’s razor doesn’t imply that actions never occur due to malice. Rather, it reasonably suggests that it’s better to assume that negative outcomes occurred as a result of stupidity, rather than malice.


  • You didn’t receive an invite to a birthday party. You assume the person intentionally excluded you, but perhaps they just forgot.

  • Your Starbucks order is wrong. You think the Barista hates you, but they likely just got the order wrong.

  • A person spills his coffee over you. You think it was intentional, but perhaps he just wasn’t looking where he was going.

Basically: relax, not everyone is out to get you.

How can I apply this?

As with all mental models, razors are used as tools to simplify, cut down, and minimize noise. They are not a substitute for critical thinking.

Use these heuristics appropriately to quickly understand root cases and accurately interpret different scenarios.

  • Hanlon’s razor can be used to bring understanding and communication to tension and conflict in relationships.

  • Media strives on dramatic and outrageous narratives. Use Hanlon’s and Occam’s razors to cut through the noise and determine your own assumptions.

  • Use Hanlon’s razor to bring peace of mind to unfavorable circumstances.

Anything else? Let me know!

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