What this country’s founders had in common was, more than anything else, the Enlightenment — an intellectual heritage that considered evidence and reason to be superior to faith, tradition, and authority as ways of understanding the world.

By 1800 the Enlightenment was already in decline, supplanted by world views that placed more stock in emotional ways of knowing.

Ten years and a day ago, 19 individuals who placed their faith in tradition and authority attacked this country, sacrificing themselves in doing so.

Their attack was, in a very real way, an attack on our Enlightenment legacy. But while much of how we responded was admirable, a re-commitment to that legacy was not part of our national conversation.

How we think about what “to know” means is very much part of the American experiment, and should not be a matter of fashion. But right now, in America, Enlightenment thinking is out of fashion.

I’ve seen first-hand an all-too-common response when someone frames problems and solutions in terms of evidence and logic: Dismissive eye-rolls by those who consider “I trust my gut” to be the alpha and omega of decision-making technique, as they explain to each other that “… of course he deals with the world this way … he is, after all, a technician, incapable of looking at the big picture.”

Here’s how bad it is: Mexico — a country with a third our population and an economy one tenth as large, has 20% more students enrolled in undergraduate engineering programs than we do. Clearly, young Mexicans see engineering as a route to affluence and respect. Young Americans consider it a path to harder work, a lower career ceiling, more limited wages, and less respect than what they can achieve through less intellectually demanding alternatives.

(They are, by the way, half right, but also half wrong. More S&P 500 CEOs earned undergraduate engineering degrees than any other major. But as a path to CEO-hood, engineering ranks below Operations, Finance, Marketing, Sales, and Planning & Development — source: “Leading CEOs: A Statistical Snapshot of S&P 500 Leaders,” SpencerStuart, 2006.)

It’s popular these days to talk about different ways of knowing as if they’re all equally valid. From the perspective of personal happiness, perhaps they are. From the perspective of career success they probably are as well, hence the well-known value of “emotional intelligence” as compared to, say, actual intelligence.

Okay, that was a cheap shot, and, worse, one that devalues an important ability –interacting effectively with other human beings.

Which doesn’t affect the point in the slightest. As evidence I offer Ben Franklin’s autobiography — a wonderful and wonderfully readable document by one of America’s leading followers of the Enlightenment. In it he offers quite a few situations that led him to discover effective principles for working with other people.

Here’s what this means: Engineers and others who base their professional success on the use of evidence and logic can use their engineering thought process to become better at interpersonals. Those who reject the “left-brain” approach to things can’t, however, use their emotional intelligence to become better engineers.

There’s a danger here: Claiming intellectual superiority over their more intuitive colleagues is an easy trap for technical professionals to fall into. Except for subjects like belief and aesthetics, evidentiary decision-making is certainly superior to intuition — the world did, after all, turn out to be round. But there’s a difference between the superiority of an approach and the superiority of the person taking it.

We’ve all been in conversations in which someone … sometimes a person with considerable experience and success … says that while they can’t explain their position, they’re pretty sure they’re right about it.

Often they are. Sometimes, the inability to explain comes from too much knowledge and experience rather than too little — the person has consciously run through the logic of similar circumstances so often that they’re no longer conscious of what they’re doing, very much as a guitar player might have a hard time explaining which fingers do what, exactly, when playing a difficult piece.

The inability to explain, that is, doesn’t make a person wrong. Unpersuasive? Yes, which is why the onus is on them to understand their internal logic well enough to explain it.

Do engineering and the other STEM disciplines (science, technology, engineering, and mathematics) belong in the Enlightenment category? Yes, of course they do, which is different from placing all scientists, technologists, engineers, and mathematicians there.

We are just as subject to human foibles as anyone else. And when we succumb to them, we are, if anything, more dangerous, because if we aren’t careful, we’ll use our expertise at applying evidence and logic to rationalize decisions we made just as irrationally as anyone else.