Deep in my dark past I was a teaching assistant for a course titled “Ecology for Physicists and Engineers.” A quiz I graded included a question along the lines of “If 84% of the population has brown eyes and 16% has blue eyes, and the gene for brown eyes is dominant, what is the frequency of the genes for blue and brown eyes in the population?”

The solution hinges on very basic population genetics, namely, knowing the binomial formula rules: x²+2xy+y²=1, where x and y are the frequencies of the genes for blue and brown eyes in the population. (Don’t worry — we’ll get to the punch line and how this connects to you in just a couple more paragraphs.)

Because the gene for blue eyes is recessive, x² percent of the population has blue eyes and 2xy+y² percent of the population has brown eyes. x² =16% (0.16) so x=0.4, leaving y to equal 1-x … 0.6.

But these were physicists and engineers, or at least they were students of the disciplines. They knew a lot of math and all, which is probably why a lot of the class, spotting the squared term in the equation, immediately hauled out the quadratic formula to solve the problem instead: x=[-b±(b²–4ac)^-0.5]/2a, never mind that this solves equations of the form ax²+bx+c=0 — an entirely different class of problem.

Some, needless to say, wanted partial credit for their answer.

Last week I proposed that we need more engineers in management, defining “engineer” as anyone who knows you can’t cool off your kitchen by leaving the refrigerator door open.

I proposed it on the theory that engineers know the difference between addressing a symptom and fixing the problem.

Regrettably, it isn’t really that simple (as if anything is). To understand the complexity, look at the interview question I suggested you add when interviewing candidates for managerial positions: “If you open the refrigerator door, how much will it cool off your kitchen?”

Like the engineers whose answers I graded in Ecology for Physicists and Engineers, it’s almost inevitable that some would answer this question by estimating the volume of air in the refrigerator, the volume of air in the kitchen, and the temperature differential (in kelvins), using them to compute the temperature of the mixed air volume.

This answer would, in fact, be accurate if you first unplugged the refrigerator, which is to say it would be correct in every detail, even though it would be completely wrong.

Lesson: No matter what type of human being we’re dealing with, we all have an unfortunate tendency to see the world through the blinders imposed by what we’re particularly good at doing. It’s the hammer/nail syndrome (if you know how to swing a hammer, every problem looks like a nail).

So if I’m a manager and I’m particularly good at extracting meaning from numbers, I’m likely to rely excessively on metrics and computer printouts, ignoring all the nuances of real-life in my department. But if I’m a more sociable type I’ll ignore the reports entirely, instead wandering around, chatting with the people I’m most comfortable with and allowing them to manipulate my perceptions to match whatever story they want me to believe.

Which gets us to the best answer to the refrigerator question — the one that tells you you’re dealing with someone who understands there’s always a backstory to the story and variations on a theme. And it isn’t an answer at all. It’s a question: “Is the refrigerator plugged in?”

There’s another trait, common among engineers, that can make those afflicted with it unsuitable for management. It’s an almost-inevitable concomitant of the problem-solving orientation that last week seemed so admirable. It’s the tendency to always see an even better alternative — to be seemingly unable to recognize when their design, code, or what-have-you has reached the exalted state of good enough.

It’s a tendency easily confused with the well-known analysis paralysis problem, or with simple perfectionism, but it’s distinct. Analysis-paralysis comes from fear of making the wrong decision, while perfectionism stems from an excessive aversion to defects.

But if you think like an engineer, spotting the even-better alternative is a matter of artistry … of design elegance … which up to a point is actually very good business.

Not all engineers recognize when they’ve passed that point, though. Which is the source of this well-known aphorism:

“There comes a point in every project when you have to shoot the engineers and put the product into production.”