Motivated Reasoning

Motivated reasoning is one of the easiest traps for an engineer to fall into.  This pleasantly oxymoronic term can be considered as an extreme case of confirmation bias.

So what is it?  I see motivated reasoning as the practice of allowing emotion to creep into the engineering process — usually through the emotion-based evaluation of data or calculations leading to an emotion-based decision.  It is a matter of putting more credence into your feelings than in the data at hand.

Now this doesn’t mean you always have to be Spock rather than Kirk, but one needs to understand that all decisions are, to a certain extent, emotional, but that one can’t dismiss engineering facts just because they don’t fit your emotional needs.

A case came up recently that illustrated this tendency perfectly.  A report generated by the best of the field offices completely disregarded a previous report from another office.  Why?  Because if that older report was true, it would mean more work and expense.  By disregarding the old data, they could avoid a lot of work and cost.  Trouble was that there was nothing really wrong with the old data.  Certainly nothing that would support tossing out the whole report.  To rationalize their position, they harped on some small errors and inconsistencies.  Their position became an emotion-driven one based on external pressures to reduce cost and schedule impact.  The correct, data-driven position was overridden.

We corrected this situation but it illustrates how easy it is, even for first-rate engineers, to fall into this trap.  Experienced engineers can sometimes go with their gut (emotions) and succeed, but when data and calculations are available, go with the math every time.  Sort of like flying in the clouds: trust your instruments and not the seat of your pants.


Remember back in the day when you could spot an engineer (or science geek) from a block away because of the tell-tale calculator on their belt?  Or going a bit further back, how they wielded their slide rule?  Okay, so neither were cool (why is wearing an iphone on your hip nowadays cool but a calculator isn’t?), but they were objects of some pride to the engineers.  A symbol, if you like, of somebody embracing math, technology, and applied science.  And of course the more complex the instrument, and the better you knew  how to use it, was the basis of some sort of hierarchy in the ranks.  Or, at least, something that earned you respect from your peers.

As a student I couldn’t afford the pinnacle of calculators, the HP-15C.   Or any of the HP products which, at that time, were the best you could get.  I had to make do with a very capable, if a little quirky, Commodore scientific calculator and a backup K-mart special.  I cared not for the TI-55 with their sticky keys.  Since then I’ve collected calculators here and there based on design and features and at work I have about four or five hanging around; more at home taking up a drawer.  My goto ones are a new HP-35S ( and an old HP-11C I recently purchased on eBay for more cash than I’m willing to admit to you.  The 11C is still, as far as I’m concerned, the second best calculator ever made and now, thirty years later, it is still a joy to use.

I guess I still think that these calculators are things of great usefulness and pride for an engineer.  And I guess that’s why it bugs me when I pass my coworker’s desks and see four-function calculators sitting there.  Have they no pride?  No sense of embarrassment that they are using a two-dollar POS that never could have gotten them through the first month in engineering school?  No desire to use or even play with the friend of the engineer?

When I asked one of them about it, he replied that he’s just a manager now, not an engineer (then what is he doing in an engineering position?).  Well, not for me.  My engineering blood still runs strong and I still carry my HP to meetings and proudly have them on my desk within easy reach.  It’s still a matter of pride to me (and usefulness) and I don’t foresee ever giving them up.

Anybody know of a belt holster for the 11C?

(Check out the HP-11C tee-shirt in the store —–>)

Tenets of Engineering Skepticism

A couple of my old posts talked about engineering skepticism (here).  I’ve been thinking more about it and came up with the following four tenets of ES.  These would be used first to test a claim, process, or machine before it could be considered useful to the engineering world.

Four tenets of Engineering Skepticism

1. The device, process, or method must be effective. It must be clear that there is a real effect without relying on advanced statistics. If the results are less than 25% better than chance (guessing), it doesn’t pass the ES test and can be dismissed as being useful to the engineering world.

2.  It must be reliable. This means that it should work the way it was intended in real life conditions and with any trained operators. If it relies on the weather, the aura of the user, or how the stars are aligned, then it fails the ES test and can be dismissed.

3.  It must be repeatable. If it is used in the same way in the same environment multiple times it should provide the same or very similar results. This should hold true even when done with different operators. For instance, if five different dowsers go through an area and give five different results, the method does not pass this ES test and can be dismissed.

4.  And it must be teachable. If it depends on some peculiar talent or right of birth then it is of no use to engineering. Knowledge must be able to be recorded and passed on to new generations of engineers.

Failure to pass all of these tenets does not necessarily mean that the device or method is fake or false, but that it is not dependable or of enough rigor to be useful to engineering. Until it meets those tenets, any engineer worth his salt will dismiss these devices or claims.

Post a comment if you think any of this makes sense, or doesn’t.


Forget about it.  If you’re looking for recognition of your efforts you need to work someplace else than the engineering field.  And why is this?  Well, two reasons: the very nature of engineers, and lousy management.

Let’s face it, engineering, while still considered a professional profession, is not given much respect in the US society.  Or, rather, it isn’t given much thought here.  They all love their cars, planes, roads, and cell phones, but they don’t have much interest in who makes all that happen.  Unless something goes wrong, of course.  Then you’ll get plenty of recognition.  The kind you don’t want.

So if you can’t find recognition outside the organization, can you find it inside?  Well, pretty much no.  Engineers who are good engineers are, for the most part, pretty bad managers.  The idea of complimenting workers, or writing them up for awards, or singing their praises to the higher-ups is not really in their nature.  There is an implicit feeling that the work should be enough.  And that there should be no ego stroking in engineering.

And this sort of works.  After all, you don’t see a flood of engineers leaving the field for more sensitive fields of endeavor.  Of course you also don’t see the quiet desparation/apathy in many engineers since they, also because of their nature, don’t advertise their feelings.

So here does that leave us?  With lots of engineers who want and need recognition working in a system where they won’t get it.  And the solution?  Well, a wise man once said to us, “You need to let the work be your reward.”  If the work alone isn’t enough to carry you through, then you’re going to have a rough time of it.

I suppose this all comes down to the difference between self-satisfaction and outside recognition.  In a perfect world the former would be enough.  For many of us, me included, we aren’t yet wise enough to not want the latter.  I hope that changes with age since equating worth by others’ opinions and actions is, I think, foolish.

Here is a quote from David Wallace’s The Pale King that might help a little:

“Enduring tedium over real time in a confined space is what real courage is.  There is no audience.  No one to applaud, to admire. No one to see you. Do you understand?  Here is the truth–actual heroism receives no ovation, entertains no one. No one queues up to see it. No one is interested.”