Why Common Sense is Not Common Practice

Knowing and doing are not the same thing. We think because we know a platitude we know how to practice it. “Treat others as you would want to be treated” seems simple enough, but as soon as we are stuck in traffic, having a bad day, or feel competitive, that platitude often goes out the window.

We assume once we learn something, which often means just reading or hearing it, we will remember and apply it in the world. Yet in the moment we respond to situations emotionally or based on habit, and our common sense gets left behind. Instincts often conflict with wisdom. And even if our judgement is sound, In the workplace or family those in power might not have common sense, making it harder for those who do have it to take action based on it. Our social nature and desire to feel safe often overrides good sense, or misshapes our perception of what is good. 

There are many books about cognitive bias. These biases are documented blind spots in how our minds work, including things like confirmation bias, or the habit of finding the first piece of data that fits our argument and looking no further. Common sense, in the abstract, dictates we should look for data that both supports and rejects a theory, as that would force thinking about how to improve an opinion (instead of merely defending an old one). But we want to be right. And we want to be efficient. Both of which work against even this simple kind of common sense.

We also forget that common sense is always changing, sometimes progressing, sometimes regressing. There can be good reasons for defying common sense as that’s what progress will feel like. There’s also the reality that in uncommon situations, common sense might not apply. There can be nuances and contexts that demand we go against what in other situations we think is right. 

A meta kind of cognitive bias is faith that knowledge of cognitive biases reduces your likelihood for having those biases. Since most cognitive biases are a side effect of how our brains function, awareness of them is often not enough to change our behavior. But we like to pretend it is. “Oh, I know about cognitive biases, so I’m immune to them now” is a fallacy. As G.I. Joe said, knowing is half the battle. The other half is often the harder one.

Common sense is not common practice.  Knowing is not the same as doing. It can take months of effort to train yourself new habits for your behavior, work that no amount of knowledge can replace. For culture to develop a new kind of common sense can take a generation. Sometimes all we can hope to do is improve our humility, as completely avoiding mistakes and failures, even common ones, is beyond us.

Also see: Why it’s ok to be obvious.


13 Responses to “Why Common Sense is Not Common Practice”

  1. Greg Linster

    Nice post! I too have noticed that many people read books like Dan Ariely’s Predictably Irrational and then think that this knowledge will help make them more rational without any practice. I’ve also noticed that most people are fond of pointing out biases in others, but not in themselves (myself included).

    How do you think the concept of “wisdom” relates to this post?

    1. Scott Berkun

      Good point about the pop psychology books – perhaps thats part of why they’re so popular. They let us think we are now better than other people because we are *aware* of these behaviors, while letting us pretend our own behaviors have magically changed.

      Self knowledge is hard to come by and that’s at the core of this thread. The Greeks would say all wisdom comes from self-knowledge (at least some of them would say that), and things like cognitive bias only provide self knowledge if we regularly use those biases as tools for sorting our what we do and why. But you can’t force someone to examine their own behavior in a book (or perhaps at all).

      1. Per Rosing Mogensen

        I think Gene Bellinger has a good framework for how data, information, knowledge, understanding and wisdom relate to each other:

        1. Data = Symbols.
        2. Information = data that are processed to be useful.
        3. Knowledge = application of data an information.
        4. Understanding = appreciation of “why” so knowledge can be adaptive and used to build new knowledge.
        5. Wisdom = evaluated understanding.

        The full explanation can be found here:

        So, I would say the pointing out behavior we all have is probably because we are at the information or perhaps the knowledge level, we see it when it’s in front of us, but we don’t really understand what its purpose is. So we attempt to quick fix the “problem”.

        I would say wisdom enters the scene when we stop looking for the quick fix localized solutions and start thinking in “global” terms of how our own thinking processes evolved throughout our lives, and relate it to how this happens for others.
        Then we will naturally seek to really understand our own and others biases, rather than judge them, in order to improve our understanding in general, as well as to be able to evaluate whether the purpose as well as immediate effect of the bias fits with our own goals.

  2. Per Rosing Mogensen

    I’d say what we know is only useful if we are aware of the knowledge at the right time, but unfortunately we often miss those moments due to cognitive “energy saving” functions, such as attentional blink, functional fixedness and the focus illusion.

    This is just a natural limitation of how our brains work, but the really sad part is when people don’t realize you can train yourself to reduce the effect of these, just like you can exercise regularly to improve your physical reaction speed, resilience and flexibility.

    Despite a lot of recent neuroscience research showing that the brain can in fact improve attention, awareness, and many other aspects that would allow us to increase our chances of focusing on the right knowledge in a given situation, it seems to me that most people still believe that it all comes down to tenacious predispositions that only specially talented individuals can hope to posses.

    Like in the physical exercise case we won’t all be super athletes, but I’m sure most people who regularly exercise say it makes quite a big difference.

  3. Sean Crawford

    I like your ending point about humility, as I see this as something that allows platitudes to sink in and be acted on. The story of my life is becoming more effective at various things the more I detach my ego with humbleness, a process that is still going on.

    Humility helps my sense of humour, which I sure need when, as you say, things are beyond me. The last thing I need is “a fragile male ego.”

    Here’s something I still chuckle over: My class wrote a mid term regarding “groups in meetings” and then some of us had to role play in front of the class. Ouch! Needless to say, we were not acting on what we had supposedly just learned. After yelling at us that we had “reverted to old behaviour patterns,” our teacher pointed out that he himself had changed –that change is not hopeless– because he kept an open mind and kept trying until the new knowledge sunk in.

  4. vivek raykar

    I have collected lot of psychology and neuroscience books in the hope that they will help me in self-improvement.But it is very tough to implement their recommendations.My brain overrides my intellect.In fact intellect is just absent when i am thick in the business of living.But still it helps to be aware of the mind science and philosophy.We can forgive ourselves and others for errors, mistakes and blunders committed by brain.Brain in history-totality knows better and pardons brain-in-present.

  5. Leo Petipas

    Isn’t there an Italian philosopher who originated this expression along with the converse?

  6. madjid

    common sense is not a common practice because peoples have not enough reason in there mind to make easy ,and lessen the situations ,there is also another problem of this people :they are not satisfied some where ,common sense is a greater understading of the reality ,it make you intache with it to make the situation simple for others because of your well understanding of the reality ,SO common sense must be a common practice for every responsible person.



Leave a Reply

* Required