[Part 2] 30 powerful razors to help you out with your decisions in life (with bonuses).

Continuation of decision-making razors with bonuses and a special razor.

For mobile users: Click ‘view entire message’ at the end of this mail to read the whole digest.

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This digest is the continuation of one of the past articles I sent earlier on Sunday.

Today I am going to give you the other half of the decision-making razors and bonus razors with an special one created by me. Stay till the end.

To recall, razors are short rules to help you simplify decisions in life.

Without any further ado, here are the other pending razors…

Note: Do not miss any “When applied practically” sections to understand the razors clearly.

16. Hume’s Guillotine (the is-ought problem)

Hume’s Guillotine principle says that you cannot decide what “ought” to be done purely from what “is.” Facts alone don’t dictate values. It simply says facts alone don’t dictate values.

The principle can be applied in any situation where facts alone can’t cover the real observation. Read the example below.

When applied practically:

You see that most of your classmates cheat in exams.

Apply the razor: That’s a fact (what is). But that doesn’t mean you ought to cheat too. The moral choice is separate from the observed behavior.

“Facts alone don’t dictate values.”

17. Einstein's Razor (related to Feynman's Razor)

Einstein’s razor principle states that everything should be as simple as possible, but not simpler. Don’t oversimplify things; it's stupidity.

This principle will be applied in study and learning, communication, and decision-making.

When applied practically:

Keeping the study notes simple and short is good, but cutting down everything and putting them in one line is stupidity.

Apply the razor: It’s about making it simple, not simpler, as it won’t sound real and teaches you nothing.

“Don’t oversimplify things; it's stupidity.”

18. New Project Razor

New Project razor says that if it’s not a “hell yes,” then it is better to say “no.” Taking one step further, if you say yes at first, imagine the project takes 2x as long and is 1/2 as profitable as you expected. Even then, if it’s a yes, then go for it.

This principle can be applied when taking on a new project and deciding whether to take it or not.

When applied practically:

You are deciding between making a mobile game you love or a boring app just for money.

Apply the razor: Pick the one you’d build even without pay—the excitement fuels persistence and better outcomes.

If it’s not a “hell yes,” then it is better to say “no.”

19. Hourly Rate Razor (Naval’s)

Hourly rate razor says value your time as if you are paying yourself an hourly rate, and avoid tasks not worth that rate. If it is important, then delegate it or automate it if possible.

This principle is used to know and value your time, so in the future you’ll be time wealthy. It promotes efficiency and maximizes your time.

When applied practically:

If you value your time at ₹500 per hour, spending 3 hours to save ₹200 on a small purchase isn’t worth it.

Apply the razor: Focus on higher-value tasks instead.

“Value your time as if you are paying yourself an hourly rate, and avoid tasks not worth that rate.”

20. Anchoring effect awareness

Anchoring effect is a principle that says the first number you see can mislead your judgment. This principle is widely used in marketing and businesses.

When applied practically:

A ₹70k laptop makes a ₹50k one seem cheap.

Apply the razor: Step back and think. Think again.

“The first number you see can mislead your judgment.”

21. Availability Heuristic awareness

Availability Heuristic principle states that just because something is easy to recall doesn’t make it likely. Things that seem hyped but are not as hyped as you think.

This principle is used when getting some news or listening to someone's views on things.

When applied practically:

There’s a plane crash in Ahmedabad, India.

Apply the razor: Plane crashes are rare even if you hear about them on the news.

“Just because something is easy to recall doesn’t make it likely.”

22. Arena Razor (Psychological razor)

Arena razor principle says that when faced with two paths, choose the one that puts you in the arena. It’s also saying listen more to those who are in the arena, actually doing the work, than to spectators giving opinions. The razor is related to the skin-in-the-game razor.

When applied practically:

You are building a startup and taking advice from people who haven’t tasted it yet.

Apply the razor: Taking advice from another founder who has struggled and launched matters more than criticism from someone who has never tried.

“When faced with two paths, choose the one that puts you in the arena.”

23. Luck Razor (related to rooms and discomfort)

Luck Razor’s principle states that when choosing between two paths, choose the path having a larger luck surface area. It says, choose the option that increases your chances of getting lucky opportunities in the future.

Applied in personal growth and success.

When applied practically:

A local tech meetup has been set in your locality.

Apply the razor: Attending it might not pay instantly, but meeting new people can open doors to unexpected internships or collaborations.

“When choosing between two paths, choose the path that has a larger luck surface area."

24. Listen Mode Razor

The listen mode razor principle states that if you encounter someone with different opinions or perspectives than yours, listen twice as much as you speak. Spend more time listening than talking when you want to learn or understand deeply.

Applied when one has to understand deeply about everything that is different from his point of view.

When applied practically:

You are in a team meeting where everyone has their own ideas.

Apply the razor: Instead of jumping in with your own ideas first, you actively listen to seniors and peers, which helps you grasp better insights and contribute wisely.

“If you encounter someone with different opinions or perspectives than yours, listen twice as much as you speak.”

25. Taleb’s Look-the-Part Test

The principle says to be skeptical of people who look and act perfectly like experts; real expertise often speaks through results, not appearances.

Apply when you are trusting one with their appearance.

When applied practically:

A trader in a flashy suit talks about easy market wins.

Apply the razor: Know a quiet, experienced investor shares verified returns. Trust the one with a proven record, not the one who only looks the part.

“If forced to choose between two options of seemingly equal merits, choose the one that doesn’t look the part.”

26. The Duck Test

The Duck Test principle metaphorically states that if it looks like a duck, swims like a duck, and quacks like a duck, it probably is a duck. When someone tells you who they are, believe them the first time.

Applied when determining a person’s character and behavior based on who he is.

When applied practically:

A coworker repeatedly misses deadlines and gives vague excuses, and others also notice the same pattern.

Apply the razor: Even if they promise improvement, their consistent actions show unreliability—treat them accordingly.

“If it looks like a duck, swims like a duck, and quacks like a duck, it probably is a duck.”

27. Gratitude Razor

Gratitude razor principle states that when comparing options, pick the one that leaves you feeling more thankful and less resentful. The rule: When in doubt, choose to show more gratitude to people who have supported and mentored you.

When applied practically:

You are offered two jobs: one pays slightly more but has a toxic environment, and the other pays a bit less but has a supportive team.

Apply the razor: Choosing the second job will leave you genuinely grateful and happier in the long run.

“When in doubt, choose to show more gratitude to people who have supported and mentored you.”

28. Smart Friends Razor (related to Optimist)

Smart Friend Razor states that if something seems crazy around, it is worth paying a lot of attention to. Spend more time with friends who are smarter than you or who challenge your thinking; they help you grow faster.

When applied practically:

You have two friend groups: one always gossips, and the other discusses ideas and skills.

Apply the razor: By spending weekends with the second group, you pick up new knowledge and improve your own thinking. It’s worth paying for.

“If something seems crazy around, it is worth paying a lot of attention to.”

29. Opinion Razor

Opinion razor states that if you can’t state the opposition’s argument properly, you haven’t earned an opinion. The rule: Charlie Munger said, I never allow myself to have an opinion on anything that I don’t know the other side’s argument better than they do.

When applied practically:

You are in a discussion about machine learning, throwing random opinions that might mislead or waste time.

Apply the razor: You stay quiet and listen to your experienced friends speaking.

“If you can’t state the opposition’s argument properly, you haven’t earned an opinion.”

30. Braggers Razor

Braggers razor principle states that trust people who quietly show results rather than those who constantly brag. Truly successful people rarely brag about their success.

When applied practically:

Two coworkers talk about their skills. One keeps boasting about being a top coder, while the other just delivers excellent projects on time.

Apply the razor: Trust the quiet performer over the loud bragger.

“Truly successful people rarely brag about their success.”

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Bonus razors (the ones I’ve missed but are equally important)

• The Invested vs. Spent test: Time is either invested or spent. Actions where time is invested compound: reading, exercising, and actions where time is spent don’t. When choosing what to do, prioritize investing time, not spending it.

• The Lion Razor: If you have the choice, always choose to sprint and then rest. When you establish fixed hours to do your work, you find unproductive ways to fill it and work longer to get less done. Sprint when inspired. Rest. Repeat.

• The Writing Knife Block: Writing is an ultimate tool to sharpen thinking—use it as a “knife block” for life. If you are struggling to understand something, try writing it out. When you write, you see the gaps that exist in your thinking. Related to Drawing Knife Block, just replace writing with drawing. Draw it out.

• Young and Old Test: Make decisions that your 80-year-old self and 10-year-old self would be proud of. Your 80-year-old self cares about the long-term value of your decision, and your 10-year-old self reminds you to stay foolish and have fun.

• The Stress Reward Test: Decide whether the stress you are taking on can be outsized when it rewards you. If not, don’t take it. Stress is only good if it has the potential to give you something rewarding.

• The Reading Razor: Never establish reading vanity metrics as goals. Read whatever you want to read that grabs you. When it stops grabbing, stop reading. Read what YOU love to read.

• Inversion Thinking: A problem-solving strategy that involves approaching challenges from the opposite direction. Rather than focusing directly on how to achieve a goal, you think about what would cause you to fail, then work backwards to avoid those pitfalls. As Charlie Munger said, “All I want to know is where I'm going to die, so I'll never go there."

• Regret Minimization Razor: This razor is introduced by Amazon’s founder Jeff Bejos. In his words, "If you’re struggling with a decision, project yourself forward to age 80. Which option will you regret not taking?" Ask: In X years, will I regret not doing this?

• The Best Story Razor: Attributed to Alex Hormozi, it states that if you’re split between two paths, pick the one with the better story. At the end of your life, it’s all you’re going to be left with.

• Pareto Principle: The Pareto principle states that your 80% outcomes come from your 20% inputs. Focus on the few things that give the most results. Eliminate or delegate the rest.

• Sunk Cost Fallacy: Don’t stick with something just because you’ve already invested in it. Past effort is not a good reason to continue with something that no longer serves you. Your old car is costing you more than a new car in maintenance.

• Positivity Razor (special razor by me): I went so fond of these razors that I ended up creating my own. The razor states that when thinking about future events, always assume positive outcomes. When you assume positive, you think positive, and positve things will happen.

Final Thoughts (Razors are short rules to simplify decision-making)

Saying it again, these razors are for simplifying your decisions in life and honing your decision-making skills. They are a rule of thumb, which means to apply them whenever required.

Remember, the goal is to simplify. Try them and find out which ones works best for you and adapt them in you daily life to make better decisions.

To get the most out of these razors, I created a handy version doc, so you don’t have to search for them again and again. Get it here: high-res printable version.

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