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11 Philosophical Razors to Simplify Your Life

Philosophical razors simplify decision-making by “shaving off” possibilities and explanations with a low probability of being useful or true. Every day we’re confronted with vast amounts of information and problems that are begging for evaluation and solutions. The ability to eliminate unlikely ones by way of taking mental shortcuts is a uniquely human superpower. From avoiding pointless arguments to handling outlandish claims and exposing deceit, I’ve put together twelve philosophical razors to simplify your life.

1. Sagan’s Standard

Extraordinary claims require extraordinary evidence.

There’s a fire-breathing dragon living in my garage. I can show it to you but it’s going to be difficult. The dragon is invisible. It doesn’t make a sound. And good luck detecting its fiery breath because it’s heatless. Just trust me on this one. Sagan’s standard rejects this kind of reasoning: The more unusual the claim, the more evidence is required to prove it and the more sceptical we should be.

How many pointless debates could be cut short by invoking this razor? It was popularised by science communicator Carl Sagan who famously coined the phrase on his program Cosmos: A Personal Voyage. The astrophysicist also came up with the dragon anecdote. “What’s the difference between an invisible, incorporeal, floating dragon who spits heatless fire and no dragon at all?” he asks in his book The Demon-Haunted World.

Sagan also put together the Baloney Detection Kit, a set of critical thinking tools that go well with Sagan’s Standard. The razor is also reminiscent of Wittgenstein’s Ruler, the idea that judgements made by an unreliable source tell you more about the source than about the claim itself.

2. Grice’s Razor

Address what someone meant to say instead of the literal meaning of the words.

Grice’s Razor is named after language philosopher Paul Grice. It’s often described as “a principle of parsimony that states a preference for linguistic explanations in terms of conversational implicature, over explanations in terms of semantic context dependence.” In simpler terms, when communicating we should be cooperative and default to generous interpretations of what someone said. What we shouldn’t do is take words out of context and rely solely on their literal meaning.

Imagine you’re at home and the doorbell rings. You call your partner who’s somewhere in the house: “Can you get the door please?” The reply comes promptly: “I’m in the shower.” Being a normal(ish) couple you go open the door yourself. A not-so-normal couple might react differently. By getting into a heated argument about how you’re supposed to “get” the door if it’s bolted to the house. And why personal shower habits are completely irrelevant to the task.

Linguists, the people who study language and its structure, distinguish between semantics and pragmatics. While the former deals with the inherent meaning of words, the latter looks at words and phrases within a context. “Getting the door” has different meanings, one of them being to open the entrance. The comment about being in the shower implies that your partner is unable to accommodate your request. Both only make sense if you take the context into account. It’s obvious in this example. The hard part is to apply it to people on social media with whom we disagree.

3. Hume’s Guillotine

What ought to be cannot be deduced from what is.

Consider the two statements 1) Carl lies about a dragon living in his garage. 2) Carl should not lie to people. The first statement merely states a fact. The second one jumps to a conclusion of what should be. It’s natural for us to make that jump. However, Hume’s Guillotine suggests that the second statement does not logically follow from the first one. The only thing that connects them is a third variable such as a moral code implicit in the statement.

Instead of jumping to moral conclusions, we should keep both, the is and the ought, strictly separate. If we believe Scottish philosopher David Hume, it’s impossible to logically derive normative or ethical statements from purely descriptive claims. Put differently, Hume’s Guillotine says we cannot derive an “ought” (a moral claim) from an “is” (a statement about the current state of things). Also known as the “is-ought-problem”, the concept goes back to Hume’s 1739 book A Treatise of Human Nature.

4. Alder’s Razor

If it cannot be settled by observation or experiment, it’s not worth debating at all.

Say you’re arguing whether a European swallow was able to carry a coconut all the way from Africa to England. It all depends on the unladen bird’s weight and airspeed velocity. You can certainly debate this issue all day long. But it’s best decided through observation. Get your hands on a few swallows and coconuts and run the experiment. Unless you enjoy having arguments for the sake of them.

Alder’s Razor serves as a guideline for swallow-related and similar intellectual discourse. It suggests that we focus on propositions that can be supported by empirical evidence rather than engaging in speculative arguments. If a claim cannot be proven or disproven by experiment or observation, where’s the point of discussing it? This way we can avoid engaging in pointless disagreements. Or in the words of the razor’s inventor, Australian mathematician Mike Alder:


In its weakest form it says that we should not dispute propositions unless they can be shown by precise logic and/or mathematics to have observable consequences. In its strongest form it demands a list of observable consequences and a formal demonstration that they are indeed consequences of the proposition claimed.

Mike Alder

It’s worth noting that Newton’s Flaming Laser Sword is the original name Alder chose. Because it was “sharper and more dangerous” than Occam’s Razor. But more on that below.

5. Feynman’s Razor

If you can’t explain something simply, then you don’t really understand it.

Acquiring all the world’s knowledge is pretty much useless if we’re unable to communicate it. By extension, if we can’t explain something in simple terms, with reduced complexity and without jargon, it probably means we haven’t understood it that well. This makes Feynman’s Razor a litmus test for comprehension.

The razor is named after physicist and Nobel laureate Richard Feynman. He was known for his exceptional ability to explain complex scientific ideas with clarity. One of his secrets is the so-called Feynman Technique. The idea behind this method is to learn about a subject matter by teaching it to others. It forces you to think through several steps of simplification and to be mindful of the language you use when explaining what you have learned.

Clear thinking starts with clear writing. Another historical figure who was in favour of simplification was George Orwell. His six writing rules encourage clarity, originality and brevity over protracted sentences and the use of obfuscating jargon. Who said simplifying your life was easy?

6. Hitchen’s Razor

What can be asserted without evidence can also be dismissed without evidence.

Aliens live among us. There’s an invisible dragon in my garage that doesn’t make a sound. Friends is better than Seinfeld. When we’re confronted with claims that lack explanations and supporting evidence, Hitchen’s Razor can make our lives easier. It echoes Sagan’s Standard and is of course named after the late British-American author and contrarian Christopher Hitchens, who used it in his book God Is Not Great.

Why waste energy on speculating and disproving assertions if those who make them have nothing to offer in their favour? You’re under no obligation to take it seriously and can in turn dismiss it out of hand. The burden of proof lies with the person who makes a claim, not the one it’s thrown at. Hitchen’s Razor is commonly seen as a play on Occam’s Razor, which goes as follows.

7. Occam’s Razor

Simpler explanations are more likely to be correct; avoid unnecessary or improbable assumptions.

Imagine it’s your lunch break. The yogurt you brought to work has disappeared from the office fridge. Did someone replace the entire fridge along with your yogurt? Is this the beginning of a sophisticated conspiratory bullying scheme courtesy of your coworkers and designed to drive you insane? There’s an infinite number of outlandish hypotheses a creative mind could come up with.

Remembering Occam’s Razor makes life easier by focusing on the simplest ones. Becoming a habitual master thinker is all about questioning your assumptions and considering multiple hypotheses to assess them based on reason and evidence. When applying Occam’s Razor we make a habit of considering the ones with the fewest assumptions or complexities as they’re generally the most reliable or likely to be true.

Also known as the law of parsimony, this is probably one of the best-known philosophical razors out there. It’s named after the medieval philosopher William of Occam who lived during the 14th century. So when you’re overwhelmed with possible explanations and your mind starts offering more, remember: Simplicity is a good heuristic to start with. Have you perhaps already eaten that yogurt yourself and forgotten about it?

8. Hanlon’s Razor

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

As it turned out, one of your dear colleagues did in fact eat your yogurt. Has your conspiracy theory been proven true? Are you dealing with a Dark Triad individual and there are malevolent forces at work? Or is the more likely explanation that your coworker didn’t know the food in the fridge wasn’t up for grabs? After all, it’s her first week and by the look of her desk, she’s rather unorganised.

Hanlon’s Razor is a reminder that not everyone is out to get us. Surely there’s evil out there. People who mislead, manipulate and play a sophisticated game of power in order to deceive. But it’s worth giving people the benefit of the doubt since forgetfulness, lack of knowledge, incompetence and stupidity are equally if not more likely explanations.

9. Riker’s Razor

If someone’s incompetence is too staggering to be true, they’re most likely faking it and you should find out why.

The team had one job. Finish that report. But all of a sudden the data analyst seems to have forgotten how to use Excel. The project manager lost the plot and your assistant suddenly has a hard time using the photocopier. Instead of getting bogged down in reteaching people their jobs, try applying Riker’s Razor. Chances are this is a feature and not a bug in their behaviour.

Riker’s Razor is my term for a principle based on an episode of Star Trek: The Next Generation. Starship Commander Riker has to deal with an unusually incompetent crew. The android Data takes way too long to compute simple questions and his engineer extraordinaire Geordi takes ages to complete a simple scan: “You’re incapable of that level of incompetence, Mr La Forge!”

Riker was right. It turns out the commander was captured by the enemy and put in a simulation designed to extract information from him. It was all a charade. While the simulation scenario is (still) unlikely in the real world, there are plenty of reasons why people would fake incompetence.

10. Jung’s Razor

If you cannot understand why someone did something, look at the consequences — and infer the motivation.

You’ve tried. But you’ve been unable to figure out why your team would go to such great lengths to fake incompetence. Time to pull out Jung’s Razor. What are the consequences of their actions? For starters, they confuse you. The report is delayed and you don’t even know if you can meet the deadline. Perhaps that’s exactly what your team wanted to achieve. They don’t believe in the work they do and want to avoid being responsible for putting together such baloney.

This philosophical razor can be traced back to Swiss psychiatrist Carl Jung. Granted, the above is not a direct quote but is said to be implicit in Jung’s writings, such as his Collected Works Vol. 4. The underlying idea is simple. Rarely can we investigate the true motivations of someone’s actions as they often lie in the unconscious. So we should judge behaviour by its results.

11. Chatton’s Anti-Razor

If three things are not enough to verify an affirmative proposition about things, a fourth must be added and so on.

Beware of monocausal explanations. Say we’re investigating the reasons behind a failed project. We’ve given all potential explanations for our failure a good “shave” and ended up with a simple answer. However, a single explanation may not entirely account for this mess. So we must add additional ones until it is fully explained. It goes to show that not all philosophical principles promise simplification.

In fact, Chatton’s Anti-Razor argues against Occam’s Razor by suggesting that seemingly unnecessary assumptions should not be eliminated without sufficient evidence. On the contrary, a thorough investigation of all relevant factors would be needed before dismissing certain possibilities. The anti-razor is named after Walter Chatton, a philosopher and contemporary of William of Occam. Simplicity alone, Chatton argued, does not guarantee the truth.

Closing Thoughts

Philosophy grapples with the fundamental nature of knowledge and existence. Philosophical razors try to make life easier through radical simplification by shaving off unlikely explanations and possibilities. How else are we going to get through the day? But as useful as they are, these simplifications remain rules of thumb and therefore not 100% accurate. So be careful not to cut yourself.