Don’t Be Tricked by These 5 Common Mental Rules of Thumb.

Every Wednesday is Tip Day.

This Wednesday: Beware of these five common heuristics.

One of my favorite topics within cognitive science is the concept of heuristics. Heuristics are the quick, commonsense principles we apply to solve a problem or make a decision.

Often, heuristics are very helpful rules of thumb, but they can also lead us to make dumb mistakes. Recognizing how heuristics operate can sometimes make it easier to be wary of the pitfalls.

Here are some common heuristics:

Recognition heuristic: if you’re faced with two items, and you recognize one but not the other, you assume that the recognized one is of higher value. If you’ve heard of Munich, Germany, but you’ve never heard of Minden, Germany, you assume that Munich is the bigger city. If you’ve heard of A Wrinkle in Time, but you haven’t heard of The Silver Crown, you assume that the first book is better than the second. When in fact they’re both outstanding children’s books!

Likelihood heuristic: you predict the likelihood of an event based on how easily you can think of an example. How worried should you be about child abduction by a stranger? What’s riskier, donating a kidney or having your gallbladder removed?

Anchor and adjust heuristic: you base an answer too heavily on some piece of first information. If someone says, “How old is Woody Allen? Twenty-five?” you’d probably guess his age to be younger than you would if someone said, “How old is Woody Allen? Ninety-five?” even though you know that both suggestions are incorrect.

Social proof: if you’re not sure about something, you assume that you should be guided by what other people are doing. You’re wondering whether to sign up for my monthly newsletter, which features highlights from the blog and Facebook. You’re not sure, but when I say, “157,000 people subscribe to it,” you think, “Yes, I do want to sign up!” You can sign up here. (End of blatant self-promotion.)

Fluency heuristic: if it’s easier to say or think something, it seems more valuable. For instance, an idea that’s expressed in a rhyming phrase seems more convincing than the same idea paraphrased in a non-rhyming phrase. When I decided to spend some time every weekend crossing long-delayed, horrible items off my to-do list,  I considered calling that time my To-Do List Time, but then switched the name to Power Hour. Much more compelling.

How about you? Do you have any examples of how you’ve used these heuristics, or other heuristics that you employ?

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  • This is a great list and I was aware of the concept behind these but lacked the name of the concepts. The anchor and adjust heuristic is perhaps the most common one for me. Even though we live in an age of where so much information is readily available when we want it, we still have to make quick judgments on small facts (that are usually of no significance.)

    One person would shout out a guess and then another, but we tend to border around the initial assumption much like the concept dictates. I’m thankful that our minds are so good at making assumptions but sometimes it does take a bit of stepping back to think on a more macro level.

  • Ahmed

    I always try to balance between choices. I try to send misunderstanding away from the “Pickup your mind” operation. and if i’m not in under the caffeine effect. and it’s not the coffee time. but it’s critical to choose or to pick up my mind, because there is no time. then I have to pick up what I know. and leave what I don’t.

  • peninith

    That ‘anchor and adjust’ thing used to be part of my efforts to get our leadership to work better with customers at a Corps of Engineers District. “Under-promise and over-deliver” was the basic advice . . . if people have ‘anchored’ their expectations to 12 weeks allowing for all the possible delaying factors, they think you have done miracles if you finish the job in six weeks. But what if you led them to expect you would be done in three weeks, assuming a best-case scenario? They will forever be ‘anchored’ to your ‘failure.’

    This ‘rule of thumb’ saying also reminds me of a wonderful AWFUL sentence I came across while editing economics texts: “We must not allow our hands to be tied by rules of thumb.” I try not to let that happen!

    • Bill Everett

      When I was in business about 30 years ago, I called this client-relations guideline “Promise the moon but deliver the sun.”

      • peninith

        Nicely calibrated!

    • Ahmed

      I think “unknown specific time missions” should not have an estimation just for the safety of you, Mission & colleagues. the word “ASAP” is the most adequate expression in these missions, if you visit shipping lines website -for example- if you are following a shipment by sea freight you will find delivery time as “ETA” which means “Estimated time of arrival”. this time has never hit it’s expectations, never in my life. usually shipments delay for more 3 days at least.

      • peninith

        Hah! you obviously do not work every day with people who deeply believe in numbers and calculations.

        • Ahmed

          Every mission in this world consist’s of 3 elements: 1- time 2- performance 3- core mission. Now if you dedicated a specific time for any given mission and prepared your self to perform well, the core mission should specify your actual mission time and performance. so try not to let colleagues know what is your core mission in each mission you perform. then you will control time and performance specifications.

  • Mike

    Power Hour! That’s worth the price of admision right there. I’d write more, but I’m heading to my…Power Hour!

  • Andrea

    If you’re interested in more “mental rules of thumb” I highly recommend “Thinking fast and slow”. Brillant information and a pageturne at the same time.

  • Janet

    Power Hour! Love it!

  • Jeffrey James

    I’m definitely guilty of falling for the anchor and adjust heuristic — sometimes it’s helpful, but other times it puts me way off the mark! I think part of the reason we rely on heuristics is because we are afraid of being wrong, which is unfortunate.

  • BKF

    It’s funny you write about this now. We were just discussing a medical problem a couple of days ago. It’s a bit fuzzy whether patients who have had strokes should continue their blood-thinners – which protect against ischemic stroke- while they have certain surgical procedures (it’s pretty clear cut for some things like dental procedures and brain surgery.) A lot of the guidelines stress that patient preference should be strongly taken into account while making the decision.The problem is that the patient is familiar with the complication they know (stroke) and they will probably say continue the medication to prevent another stroke since they have not experienced the bleeding complication yet from the blood-thinners. But physicians have seen both so they are usually more cautious. Thanks for this great post, Gretchen!

    • Alissa Ripley

      I agree, I’m usually super cautious, we hear about child abductions quite often, so I tend to have that as my brain’s problem!

  • Todd

    These examples outline the various ways you may break one of the most important agreements of the Four Agreements (Don’t Assume) (book on Toltec Wisdom by Don Miguel Ruiz). Your examples are great illustrations of how complex the Don’t Assume agreement can be.

    For reference: the other 3 are:

    * Integrity of Your Word

    * Do your Best

    * Don’t Take it Personally.

    I find these to be a powerful foundation for finding happiness in life. Lack of happiness usually (not always) correlates to breaking one of these agreements. We even manage our company on these principles!

    • peninith

      “Don’t Assume” is, I have learned, the one I most have to attend to. It also means to me ‘Don’t INTERPRET’ . . . I have in the past been very given to letting scenarios or ‘meanings’ metastasize in my head until they become full blown, detailed worry plots that have little to do with anything but some tiny seed of worry in my own mind. A good reminder. Thanks.

  • Oh, I love The Silver Crown. Great book. 🙂

  • Jeanne

    Great food for thought. We would not be able to function in the world without our brains filtering out a lot of incoming stimulus and making decisions quickly and based on past experience, but slowing down and making more conscious choices is always better if possible. Are you watching “Brain Games” on the National Geographic Channel? You would LOVE it. The way our brains process information is fascinating, and some things we can’t override. I got the shingles all over my scalp and face right after quitting a medication. Were the two related? I don’t know. Will I EVER stop that medication again? NO. Is that a rational decision? I don’t know. All I know is that I never want to have the shingles again, and any side effects from staying on the medication don’t seem as terrible as another shingles outbreak. But I can’t really know that. – P.S. Everyone over 60, please get the shingles vaccine. You DO NOT want to have shingles.

  • Paul Edward Carkhuff

    I just joined the Happiness Project, and asked myself, “why?” I answered myself as I often do. Who doesn’t want to be happy? Duh!! That and it’s free:)

  • KDfrAZ

    Your example on the likelihood heuristic made my eyes pop wide open. 🙂 I’ve never KNOWN a kidney donor…. while I honor people who donate kidneys (especially to strangers!), I’ve never personally known anyone who has done so. OTOH, I’ve had several friends go through gall bladder removals, with no problems or complications.

    Since I was accustomed to seeing positive effects for the gall bladder removal, I assumed it was the safer option. And as you said, this is based on that likelihood heuristic: I can call examples of gall bladder removal to mind by NAME, and can only think of vague newspaper stories or the like for kidney donors. Therefore the familiar, the more “likely” to my mind, probability is for the transplant to have FAR more dangers.

    Thanks for pointing this one out for me!

  • Good points! Anchor and adjust is why first impressions are so important.

    To your briliance!