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What Do You Think You Know and Why Do You Think You Know It?

2010 January 24

Many people who like to think they take a pragmatic view miss out on the reality of the way things actually work.  Many of the most useful ideas are also the most bizarre.

It is through the improbable that we achieve the practical.

Take GPS, for example, which is an amazing application of cutting edge technology for everyday use.  It makes our lives easier and improves our productivity in countless ways by giving us incredibly accurate readings of distance and projecting those estimations onto a map.

However, GPS only works the way it does through the rejection of the concept of distance itself.  Ironically, it is, in fact, the denial of certainty that makes the measurements so reliable.

To see how, let’s look at the chain of thought that began in the late Renaissance and led through Hume and Einstein to give us the technology we enjoy today.

Hume’s Skepticism

Will the sun rise tomorrow?

David Hume dared to ask that question.  While not a household name, Hume was a contemporary and good friend of Adam Smith while also an eminent philosopher and economist himself.

His major work, A Treatise of Human Nature, argued for the primacy of experience over rational thought and is considered the greatest exposition of empiricism.  Although Hume rejected the Cartesian rationalism that was still influential at the time, he did accept Descartes’ assertion that our perceptions are unreliable.

In other words, he believed that all that we know we get from our experiences, but that our experiences don’t tell us much.  The consequence is radical skepticism. Hume argued that even our expectation that the sun will rise tomorrow is the result of habit and expediency rather than of certainty.

We do, as a matter of practice, accept many ideas without actually knowing they are true.  People tell us things and, if they don’t directly conflict with our experience, we tend to believe them.  That doesn’t mean that we really know what we’re talking about.

Einstein’s Relativity

One of Hume’s most ardent fans was Albert Einstein, who counted Hume among his greatest influences.  It was his adoption of Hume’s skeptical view that allowed him to question the concept of absolute time and space.

Once he was able to discard what his immediate experience told him was true, he was able to achieve insights that would reorder the universe into a place where time and space are relative.  He showed that much of what we regard as hard fact is actually a matter of perspective.  The measurements we use here on earth don’t hold sway in the rest of the universe.

This gave way to even more bizarre discoveries that defy common sense.  Gravity doesn’t pull, but pushes.  Time travel is possible.  Teleportation is actual (first performed at IBM laboratories in 1993).  We advance our society by bringing unreality into everyday life.

How GPS Works

GPS is a network of satellites that orbit the planet.  For any given point, three satellites are used to triangulate the position and send the information to computers here on earth.  There is a direct line from Hume to Einstein to thousands of other very smart people that makes it all possible.

Relativity only seems strange to us because we are a special case.  We live in a world where objects are neither very big nor very small and nothing moves even close to the speed of light.  We don’t need to account for relativity in everyday life.

Of course, we also do not run into GPS satellites walking down the street.  They don’t care what we “know” to be true.  GPS depends on incredibly accurate clocks which do, in fact, run slightly slower than the ones down here on earth at precisely the rate that Einstein’s equations predict.

If that difference isn’t allowed for we would be hopelessly lost.

The Crazy Ones

It is our natural inclination to rely on our experience that leads to our misguided tendency to believe everything we think.  If the world really worked the way we suppose it does, then further advancement would be impossible.  In our ignorance lies the promise of better things.

While practical men achieve practically nothing, it is “the crazy ones” that are willing to believe the unbelievable who move us forward.

So the next time you’re rushing to a meeting and can’t afford to get lost, you can gain some comfort from the device that will guide your way.  It will not only lead you to your destination, but hopefully to an important question.

What do you think you know and why do you think you know it?


20 Responses leave one →
  1. Stirling permalink
    January 24, 2010

    Interesting article- thanks Greg – but not sure I agree with it all. I think one of the reasons why the world is very different from the way we see/perceive it is because there are very big and very small objects. Infinity stretches both ways and our normal measures and understandings are ruptured in trying to make sense of it all. All great fun though! Stirling

  2. January 25, 2010


    I mostly agree with that and actually used almost those same words in the article:

    “Relativity only seems strange to us because we are a special case. We live in a world where objects are neither very big nor very small and nothing moves even close to the speed of light. We don’t need to account for relativity in everyday life.”

    But there are other reasons why induction fails us as well. It’s easy to mistake our own unique perspective for a universal truth. If all we’ve ever seen is white swans it’s hard to imagine a black swan.

    – Greg

  3. January 25, 2010

    Another interesting post, Greg, thanks!
    Seems to me one learns something new only when one opens one’s mind and asks the question “why?” Which is another way of saying that before you can learn something, you have to be uncertain enough about what you think you know, to ask the question you ended your post with,” What do you think you know and why do you think you know it?” If you never ask this question, you are by definition assuming that you know the answers and if your assumption is false you will never find out the truth.
    And just for the record; GPS systems need at least 3 satellites to triangulate a fix, but will use all that lie within “sight” of the receiver on the ground – sometimes as many as 8. I know this from my days of sailing oceans when the GPS on board would display the number of satellites in “view” at any given time. There are I believe 24 satellites in the system overall.

  4. January 25, 2010

    If all we know is what we think we know or based on what has happened in the past or what typically happens, then absolutely nothing new would ever evolve. I often find it ironic in corporate life when the phrase “thinking outside of the box” is thrown around like an old baseball. Most corporate structures don’t allow for such thinking, they like to think they do, but in actuality, innovative thinking within a corporate structure is often an uphill battle. The most successful companies are those that are able to embrace and truly welcome innovative thinking and allow it to permeate the entire structure of an organization. Again, Apple is a fine example of that. Nothing is finite, ideas which lead to endless possibilities and new realities keep coming if you let them.

  5. January 25, 2010


    Thanks for your comment. Cogent as always.

    I didn’t know about the extra satellites that can be used to “fix.” Are you sure that all of them are used? It seems to me that it would just complicate the calculation without actually getting better accuracy. It’s an interesting question that I don’t know the answer to.

    Apparently the whole network is 24-32 satellites, which I guess means they keep some redundancies but 24 is the minimum.

    – Greg

  6. January 25, 2010


    You hit the nail on the head. Once you are managing more than a few hundred people, it becomes extremely difficult to find a good balance between innovation and consistency.

    I think the greatest management model ever invented is the one Tim Berners-Lee came up with for the web. A minimum amount of simple rules govern the entire web and it all works.

    Another good rule of thumb is to always abide by the “Hobbesian Paradox” that says that rules are only enforceable if the overwhelming majority is willing to follow them. Too many companies end up spending too much time trying to enforce unenforceable rules and stifling creativity and innovation.

    – Greg

  7. January 26, 2010

    Hi Greg, We’re celebrating the birth of our nation here in Australia today, relative to the summer heat, beach picnics, bbq’s, and parties.
    But on a more Einstein serious note did you know that organisational development is a bit like a GPS navigation system for leaders? and what might you think a model of leadership development relative to return on investment measured on three levels might be worth???

    happy holidays

  8. January 26, 2010

    Hi Kylie,

    nice to see you again.

    – Greg

  9. Peter permalink
    January 26, 2010

    I’ve always found the biggest problem is not thinking laterally or radically, but persuading others to see your vision.

    Consultants are particularly prone to this. From outside you can see exactly what needs to be done to transform the profitability of a company, but communicating that to the people in that company is well nigh impossible (otherwise they would be doing it).

    Any ideas for not only having the idea but communicating it?

  10. January 26, 2010


    Well the first thing is to ask yourself why you are so sure that your solution is the right one and why you are getting so much resistance.

    The best way to do that is to listen and learn what their objections are. If you can address their concerns and show the benefits of what you are proposing, there is no reason they wouldn’t want to implement your ideas.

    If you want to gain trust, you have to give it first.

    – Greg

  11. January 26, 2010

    Greg, Peter,
    I have run into this problem not only as a consultant, but while working in-house and in my own venture as well with my own business partners. Spent some very frustrating meetings, that were exercises in futility, not due to my lack of backing evidence, knowledge or understanding, but due really to a lack of shared brand vision. Greg, I think your response is correct assuming that all involved are open minded, are all working toward the same goal and share the same vision- again if it’s a healthy modern company that insists on letting innovation permeate every level of the organization. Unfortunately in many cases, those elements are not in place and it becomes an issue of simply not speaking the same language. For me, it often boils down to a right brain, left brain thing. Either you get it or you don’t depending on how your brain works and how you think. Not sure in many instances that there is an easy solution.

  12. January 26, 2010


    As usual, you make some very good points.

    However, I’ve found that it is very important to listen and learn why they object. Usually, there is a good reason (and I’m talking from experience in some rough places and some very nasty people).

    If you at least understand what the problem is (for instance, the guy is corrupt and have people killed on a regular basis, so certainly doesn’t have to listen to you) you can at least figure out how to deal with it. It’s much better than shooting in the dark.

    – Greg

  13. January 26, 2010


    Excellent read and very eye opening. Everyone likes to use the phrase ‘think outside the box’ but few actually do it. And the ones that do change the world.


  14. January 26, 2010


    Thanks. I’m glad you liked it:-)

    – Greg

  15. January 27, 2010

    Some great comments here!! Rearead your post and now understand what you meant Greg on the reality of very large and very small objects. The point is that in business true breakthrough moments happen rarely. It is easier to be risk adverse, to continue in the way things have always been done and to go only with the 80% then to seek new ways/methods/products/approaches.
    Very few of us do this in our private lives so to expect others to do it in business is fanciful. For me I appreciate true creativity and when it happens in art, music, literature, design or business its to be applauded and encoraged.

  16. January 27, 2010


    I agree. Most of success is just grinding it out and creativity research shows that innovation is the same way.

    Apparently the key creativity factors are:

    1. Domain Knowledge: You have to know your field well if you are going to add something useful too it.
    2. Productivity: The more work, the more great work.
    3. Useful analogues – Quite often great solutions are found by borrowing a solution from a different context and applying it in a new way.

    By my count, that’s about 2/3 of grinding it out:-)

    – Greg

  17. January 27, 2010

    A great book to check out is ‘The War of Art’ by Steven Pressfield. Mainly creativity comes to those that work. You can’t do something great if you don’t do something first.

  18. January 27, 2010


    Thanks for the tip. I’ll check it out.

    – Greg

  19. Charity Collins permalink
    October 15, 2012

    This article really makes me wonder what I actually know. As stated I question things that don’t go along with my personal experiences, but that’s creates a problem when something is true about my experiences is not necessarily the truth. This means we ONLY KNOW WHAT WE THINK WE KNOW. It’s from irrational thinking that gives us the best ideas and new discoveries. I can also see how this article could leave somebody uneasy if they take too personal also.

  20. October 15, 2012

    As beautifully expounded upon in Antonio Damasio’s book, “Descartes Error”, sensory perceptions are far too subjective to be utilized as a primary form of “knowing what we know” – physiological limitations, psychological “filters” and the like play far too large a role in what we “think” we know. Hume’s reliance on empiricism / experience is, thus, substantiated in his subsequent book, “The Feeling of What Happens,” corroborating Hume’s ideology through the sciences of neurology and psychology. Given the now common knowledge that 90% of cognitive activity occurs at a subconscious level, I am of the opinion that we can never really *know* what we think we *know – it is for this reason I choose to focus my academic and life goals on Eastern ideologies which, for me, are the most evolved methodologies for “knowing” what we “know.”

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