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First principles

Reason up from what is known to be true, not from what is usually done or said.

Our reading of the idea · 14 claims from 5 people, in their own words

Physics teaches reasoning from first principles rather than by analogy.

  1. Elon Musk Founded SpaceX in 2002 And physics teaches you to reason from first principles rather than by analogy. Elon Musk's Mission to Mars (WIRED interview with Chris Anderson)wired.com · 21 Oct 2012All korrents from this piece
    And physics teaches you to reason from first principles rather than by analogy.

Reasoning from first principles means gathering only what one knows to be true and building a conclusion from it.

  1. Tim Urban Writer and illustrator behind Wait But Why A scientist gathers together only what he or she knows to be true—the first principles—and uses those as the puzzle pieces with which to construct a conclusion. The Cook and the Chef: Musk’s Secret Saucewaitbutwhy.com · 6 Nov 2015All korrents from this piece
    A scientist gathers together only what he or she knows to be true—the first principles—and uses those as the puzzle pieces with which to construct a conclusion.

Reasoning from first principles means taking the basic raw ingredients as the building blocks and working upward from them.

  1. Tim Urban Writer and illustrator behind Wait But Why The chef reasons from first principles, and for the chef, the first principles are raw edible ingredients. Those are her puzzle pieces, her building blocks, and she works her way upwards from there, using her experience, her instincts, and her taste buds. The Cook and the Chef: Musk’s Secret Saucewaitbutwhy.com · 6 Nov 2015All korrents from this piece
    The chef reasons from first principles, and for the chef, the first principles are raw edible ingredients. Those are her puzzle pieces, her building blocks, and she works her way upwards from there, using her experience, her instincts, and her taste buds.

Good ideas come from asking how you would solve a problem from first principles, rather than staying anchored on how it is solved today.

  1. Jeff Dean Chief Scientist at Google DeepMind and Google Research you know, because sometimes if you just squint at a problem and you think about not necessarily being anchored on exactly how that problem is solved today, but how you would solve it from first principles, you can come up with really good ideas that are, you know, maybe not what other people are thinking about. Jeff Dean: The 1% Rule for Building in AIyoutube.com · 30 Jul 2026 · 10:05 into the videoAll korrents from this video
    you know, because sometimes if you just squint at a problem and you think about not necessarily being anchored on exactly how that problem is solved today, but how you would solve it from first principles, you can come up with really good ideas that are, you know, maybe not what other people are thinking about.

    Watch from 10:05 plays here

    ↗Jeff Dean: The 1% Rule for Building in AIyoutube.com

    30 Jul 2026 · video · 57m · spoken · machine transcript

People in industry routinely short-circuit their reasoning, adopting what they heard in a conference talk instead of thinking it through from first principles.

  1. Martin Kleppmann Computer science researcher at Cambridge Often people in industry I feel like sort of have short circuit reasoning. Like don't maybe don't quite reason something through from first principles but just like oh I heard this from a conference talk I'm just going to go with that Designing Data-intensive Applications with Martin Kleppmannyoutube.com · 22 Apr 2026 · 1:23:42 into the videoAll korrents from this video
    Often people in industry I feel like sort of have short circuit reasoning. Like don't maybe don't quite reason something through from first principles but just like oh I heard this from a conference talk I'm just going to go with that

    Watch from 1:23:42 plays here

    ↗Designing Data-intensive Applications with Martin Kleppmannyoutube.com

    22 Apr 2026 · video · 1h 25m · spoken · machine transcript

The best scientists ask the simplest questions, because they never lie to themselves that they understand something they do not.

  1. Janna Levin Theoretical cosmologist The best scientists I know often ask the simplest questions. First of all, there’s probably some confidence there, but also they’re never going to lie to themselves that they understand something that they don’t understand. Janna Levin: Black Holes, Wormholes, Aliens, Paradoxes & Extra Dimensions | Lex Fridman Podcast #468youtube.com · 5 May 2025 · 1:05:03 into the videoAll korrents from this video
    The best scientists I know often ask the simplest questions. First of all, there’s probably some confidence there, but also they’re never going to lie to themselves that they understand something that they don’t understand.

The raw-materials cost of a rocket is only around 2 percent of the typical price of one, an unusually low ratio for a large mechanical product.

  1. Elon Musk Founded SpaceX in 2002 It turned out that the materials cost of a rocket was around 2 percent of the typical price—which is a crazy ratio for a large mechanical product. Elon Musk's Mission to Mars (WIRED interview with Chris Anderson)wired.com · 21 Oct 2012All korrents from this piece
    It turned out that the materials cost of a rocket was around 2 percent of the typical price—which is a crazy ratio for a large mechanical product.

A person who works from a recipe, even an innovative one, starts from something that already exists.

  1. Tim Urban Writer and illustrator behind Wait But Why But what all of these cooks have in common is their starting point is something that already exists. Even the innovative cook is still making an iteration of a burger, a pizza, and a cake. The Cook and the Chef: Musk’s Secret Saucewaitbutwhy.com · 6 Nov 2015All korrents from this piece
    But what all of these cooks have in common is their starting point is something that already exists. Even the innovative cook is still making an iteration of a burger, a pizza, and a cake.

Conventional wisdom lags behind reality, so someone who looks at the present directly can act on information others have not yet been given permission to act on.

  1. Tim Urban Writer and illustrator behind Wait But Why Conventional wisdom is slow to move, and there’s significant lag time between when something becomes reality and when conventional wisdom is revised to reflect that reality. And by the time it does, reality has moved on to something else. But chefs don’t pay attention to that, reasoning instead using their eyes and ears and experience. By ignoring conventional wisdom in favor of simply looking at the present for what it really is and staying up-to-date with the facts of the world as they change in real-time—in spite of what conventional wisdom has to say—the chef can act on information the rest of us haven’t been given permission to act on yet. The Cook and the Chef: Musk’s Secret Saucewaitbutwhy.com · 6 Nov 2015All korrents from this piece
    Conventional wisdom is slow to move, and there’s significant lag time between when something becomes reality and when conventional wisdom is revised to reflect that reality. And by the time it does, reality has moved on to something else. But chefs don’t pay attention to that, reasoning instead using their eyes and ears and experience. By ignoring conventional wisdom in favor of simply looking at the present for what it really is and staying up-to-date with the facts of the world as they change in real-time—in spite of what conventional wisdom has to say—the chef can act on information the rest of us haven’t been given permission to act on yet.

Conventional wisdom assumes things are the way they are for a good reason, and history repeatedly proves status quo dogma wrong.

  1. Tim Urban Writer and illustrator behind Wait But Why Conventional wisdom worships the status quo and always assumes that everything is the way it is for a good reason—and history is one long record of status quo dogma being proven wrong again and again, every time some chef comes around and changes things. The Cook and the Chef: Musk’s Secret Saucewaitbutwhy.com · 6 Nov 2015All korrents from this piece
    Conventional wisdom worships the status quo and always assumes that everything is the way it is for a good reason—and history is one long record of status quo dogma being proven wrong again and again, every time some chef comes around and changes things.

If a chain of reasoning rests on a wrong inherited recipe, the conclusions built on top of it will be just as wrong.

  1. Tim Urban Writer and illustrator behind Wait But Why And if the tenets of that church don’t truly resonate with you or reflect the current reality of the world—if it turns out that you’ve been working off of the wrong recipe—then whatever conclusions have been built on top of it will be just as wrong. As demonstrated by the flood geologists, a reasoning chain is only as strong as its weakest link. The Cook and the Chef: Musk’s Secret Saucewaitbutwhy.com · 6 Nov 2015All korrents from this piece
    And if the tenets of that church don’t truly resonate with you or reflect the current reality of the world—if it turns out that you’ve been working off of the wrong recipe—then whatever conclusions have been built on top of it will be just as wrong. As demonstrated by the flood geologists, a reasoning chain is only as strong as its weakest link.

Dogma, unlike first-principles reasoning, is not customized to the believer or meant to be critiqued and adjusted as things change.

  1. Tim Urban Writer and illustrator behind Wait But Why Dogma, unlike first principles reasoning, isn’t customized to the believer or her environment and isn’t meant to be critiqued and adjusted as things change. The Cook and the Chef: Musk’s Secret Saucewaitbutwhy.com · 6 Nov 2015All korrents from this piece
    Dogma, unlike first principles reasoning, isn’t customized to the believer or her environment and isn’t meant to be critiqued and adjusted as things change.

At many big companies, process becomes a substitute for thinking.

  1. Elon Musk Founded SpaceX in 2002 The problem is that at a lot of big companies, process becomes a substitute for thinking. Elon Musk's Mission to Mars (WIRED interview with Chris Anderson)wired.com · 21 Oct 2012All korrents from this piece
    The problem is that at a lot of big companies, process becomes a substitute for thinking.

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