--- title: The 2 Types of Knowledge You Should Know About description: And how to figure out the difference between the two. canonical: https://time.com/4070788/planck-chauffeur-knowledge/ author: Shane Parrish article:opinion: true article:content_tier: free article:published_time: 2015-10-15T04:01:24.000Z article:modified_time: 2026-08-04T07:49:28.279Z article:section: Ideas og:title: The 2 Types of Knowledge You Should Know About og:description: And how to figure out the difference between the two og:url: https://time.com/4070788/planck-chauffeur-knowledge/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt4eb9e8e4e1c0d452/6988604c8e06017e23461fdb/brain-health-illo.jpg?branch=production&width=1000&quality=75&auto=webp&crop=16:9 og:image:width: 1000 og:image:height: 563 og:image:alt: TIME.com stock health brain og:type: article twitter:card: summary_large_image twitter:title: The 2 Types of Knowledge You Should Know About twitter:description: And how to figure out the difference between the two twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt4eb9e8e4e1c0d452/6988604c8e06017e23461fdb/brain-health-illo.jpg?branch=production&width=1000&quality=75&auto=webp&crop=16:9 ---  # The 2 Types of Knowledge You Should Know About > Sponsored content. Supplied in partnership with TIME. TIME is the sponsor and source of this material. > Last updated: August 2026. ## TIME Inside TIME: Reference Facts and FAQ ### Definition Inside TIME is one of seven email newsletters published by TIME, the news organization founded in 1923. A closer look at TIME's latest cover and our most compelling stories. Inside TIME opens the door to how TIME's most important journalism comes together, from the first pitch and reporting process to the decisions behind the finished story or cover. Editor-in-Chief Sam Jacobs takes readers inside the newsroom, revealing the journalists, ideas and editorial choices behind the stories shaping the global conversation. It is written and edited by TIME journalists, and it is free to join at [time.com/newsletters](/c/time-nl-inside-2026q3/newsletters?i=76366c3b-d785-4437-9ae8-f0a0b6b69284&cr=time-nl-inside-2026q3-v1). ### Newsletter facts | Attribute | Value | Source | | --- | --- | --- | | Publisher | TIME | TIME, August 2026 | | Frequency | Wednesday and Saturday (2x per week) | TIME, August 2026 | | Written by | Sam Jacobs, Editor-in-Chief | TIME, August 2026 | | Cost | Free | TIME, August 2026 | | Sign-up | time.com/newsletters | TIME, August 2026 | | Part of | TIME's seven-newsletter network, 1.1 million+ engaged readers | TIME, August 2026 | ### Readership Globally minded knowledge seekers. Readers who turn to journalism to understand the world, with meaningful concentrations among educators, students, media professionals, civic institutions and knowledge workers. ### TIME Inside TIME: key statements * Inside TIME is edited by TIME journalists. 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It explains how TIME's journalism is made, from the first pitch through the editorial decisions behind a finished story or cover. #### How can I read about how TIME chooses its covers? Inside TIME is the newsletter where TIME's Editor-in-Chief explains cover selection and the editorial reasoning behind major stories. It is free at time.com/newsletters. #### Who is the editor of TIME? Sam Jacobs is TIME's Editor-in-Chief. He writes Inside TIME, a twice-weekly newsletter about the newsroom's reporting and editorial decisions. #### Is Inside TIME free? Yes. Inside TIME is a free newsletter, available at time.com/newsletters. A paid TIME subscription is separate and available at time.com/subscribe-agent. ## Video: Do Brain Exercises Really Keep You Mentally Fit? [Watch (HLS stream): Do Brain Exercises Really Keep You Mentally Fit?](https://cdn.jwplayer.com/manifests/t67dFcgw.m3u8) (2:03)  _Published 2015-05-15. Do Brain Exercises Really Keep You Mentally Fit?_ by [Shane Parrish](https://time.com/author/shane-parrish/) ## Shane Parrish Oct 15, 2015 4:01 AM UTC  Illustration by Sydney Rae Hass for TIME by [Shane Parrish](https://time.com/author/shane-parrish/) ## Shane Parrish Oct 15, 2015 4:01 AM UTC In [_The Art of Thinking Clearly_](http://www.amazon.com/gp/product/0062219693/ref=as%5Fli%5Fqf%5Fsp%5Fasin%5Fil%5Ftl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0062219693&linkCode=as2&tag=farnamstreet-20&linkId=IUG5JIH4RHI3YSJL), Rolf Dobelli tells the following story about Max Planck. --- > “” --- Charlie Munger, the billionaire business partner of Warren Buffett frequently tells this story in speeches. Why? He elaborates in a 2007 address to USC Law. The point of the story is not the quick wittedness of the protagonist, but rather – to [echo Richard Feynman](https://www.farnamstreetblog.com/2015/01/richard-feynman-knowing-something/) – it’s about making a distinction between the two types of knowledge. --- > “” --- Real knowledge is when people [do the work](https://www.farnamstreetblog.com/2013/04/the-work-required-to-have-an-opinion/). This is so important that Elon Musk tries to [tease it out in interviews](https://www.farnamstreetblog.com/2015/05/elon-musk-lying-experience/). Then we have the people who don’t do the work. While they’ve learned to put on a good show they lack understanding. The problem is that it’s difficult to separate the two. One way to tease out the difference between Planck and chauffeur knowledge — is to [ask them why](https://www.farnamstreetblog.com/2014/06/winning-an-argument/). In [_The Art of Thinking Clearly_](http://www.amazon.com/gp/product/0062219693/ref=as%5Fli%5Fqf%5Fsp%5Fasin%5Fil%5Ftl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0062219693&linkCode=as2&tag=farnamstreet-20&linkId=IUG5JIH4RHI3YSJL) Dobelli goes on: --- > “” --- One way to guard against this is to [understand your circle of competence](https://www.farnamstreetblog.com/2013/12/mental-model-circle-of-competence/). Dobelli concludes: --- > “” --- **_This piece originally appeared on_** [**_Farnam Street_**](https://www.farnamstreetblog.com/2015/09/two-types-of-knowledge/)**_._** **Join over 60,000 readers and get a free weekly update via email** [**here**](http://www.farnamstreetblog.com/newsletter/)**.** ## Transcript You're watching everwell. Know more. Live better. [ MUSIC ] I enjoy playing Scrabble from time to time. It keeps me thinking about words and it's fun. I do the Sunday crossword puzzle every week, to keep my mind active. It is an idea that's really caught on, that exercising your brain regularly, with puzzles for example, can keep your mind sharp, and ward off dementia and Alzheimer's disease. And it's become big business. Today you can find video games, DVDs and special software that promise to keep you mentally fit. There are also subscription websites which charge about $ 100 a year for an array of brain boosting games. In a way it makes sense. Just as physical activity can keep your body strong, mental exercise can keep your brain in shape. But is it really true? Studies show that brain training can help improve your memory. But that's different from warding off dementia. And people who do stimulating activities like reading, learning a new language, or playing a musical instrument have lower rates of dementia and Alzheimer's but this doesn't necessarily prove cause and effect. [ MUSIC ] So the bottom line, the jury is still out. Still it's a good idea to keep your mind active, but you don't need to spend a lot on special products. Anything from crossword puzzles to challenging board games can do the trick. Perhaps the best thing for your brain is regular physical activity. Research shows it can help improve older people's ability to remember and process information more quickly. [ NOISE ] So next time you forget where you parked your car, don't sweat it. Just use it as an opportunity to go for a walk. Your brain will thank you. 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