[​​Brown Belt] Appreciating personality differences will help you work more effectively with others.

One thing about personalities is obvious: not everyone is like you. But perhaps not so obvious is that there are various measures of personality that can quantify just how much everyone is not like you.

One very common measure is known as the Myers-Briggs Type Indicator,^[36] which measures how people perceive the world and make judgments. You can take a test to determine your MBTI, and it would certainly be handy to know the MBTIs of people you work with, but those are luxuries you probably won’t get.

What’s more important is to understand the factors Myers-Briggs—or other personality measurements—and use those to assess the people around you based on observation. You may not guess their types exactly, but you can get close enough. If you get a rough picture of how you deal with the world and how they deal with it, it can help you to relate to that person in a meaningful way.

Temperament: Introversion/Extroversion

The first type measurement is the scale between introversion and extroversion: inward-facing vs. outward-facing. These are terms you’ve likely heard before, and you can probably put yourself on the scale quite readily. In very general terms:

• Introverts recharge their batteries with alone or one-on-one time; engaging with a larger group drains their energy. They seek depth of knowledge and apply intellect before action.

• Extroverts recharge by spending time with people; alone they stagnate. They seek breadth of knowledge and apply action before intellectual reflection.

Introverts and extroverts can get along well when they appreciate each other’s strengths. For example, programmers and salespeople tend to be polar opposites on this scale, but find two who respect each other and present a united front, and you have a force to be reckoned with. In fact, some of my best professional work was done in partnership with a business development guy—he’d herd the personalities; I’d take care of the technology side.

What’s not so obvious about the I/E scale is that it’s not the same thing as comfort in dealing with other people. We have a view of introverts as shy and extroverts as gregarious. That’s not necessarily true. Introverts can be outgoing and expressive. Extroverts can be reserved.

I’m an introvert; I nearly pegged the scale in my MBTI test. However, as I’ve grown older, I’ve become much more outwardly expressive. This is partly a matter of training—trade shows are great for developing your skill in starting a conversation and quickly finding common ground with a complete stranger.

Perceiving: Sensing/Intuition

The next scale deals with how a person gathers data: sense (or data) driven vs. intuition and association. This parallels the L-mode and R-mode styles of thinking,^[37] often referred to as “left brain” for linear and logical thought vs. ”right brain” for pattern recognition and artistic skill. In general terms:

• People relying on sensing need to look at the data—possibly “data” from all five senses depending on what they’re perceiving—and extract meaning from those sources. This is primarily an L-mode activity, using the sequential, reasoning part of their brain to put together the picture of what’s going on.

• People relying on intuition will rely on less data but couple it with their instinctive reaction to the data they have. This isn’t the same as a wild-ass guess—that instinct is coming from the brain, just another part. It’s R-mode thinking, where the asynchronous, pattern-matching part kicks in and gives them that “flash” of insight.

The difference between these modes of thinking is exquisitely illustrated in Malcolm Gladwell’s Blink [Gla06], where he discusses the ability of art experts to sniff out forgeries. Some take the sensing approach, going so far as to write software that brings statistics to bear on analyzing a suspect painting vs. a reference library of known authentic paintings, looking at details like stroke lengths and density. With enough data points, they can model a painter’s style and sniff out fakes that may look visually identical—almost.

Other art experts can look at a suspect painting and intuitively know whether it’s real or a fake. They’re not just flipping a coin—whether they know it or not, they’re using the pattern-matching engine in their brain, trained with decades of experience. In effect, they’ve built up their own statistical models. They can’t tell you in rational terms how they do it; they just intuitively know a fake when they see it. And usually they’re right.

How does this guide your interactions with others? Let’s say you’re trying to track down a bug. You’re the data-driven type and you’re working with an experienced co-worker who relies on intuition. If he says, “Hmmm… let’s go poke in this other module” but can’t explain why, try humoring him rather than pushing back. Just because he can’t explain it doesn’t mean there isn’t real thought behind it—it’s just thought from a different part of the brain than linear, logical thought. And if the hunch doesn’t pan out, go collect some more data.

Note that most people tend to fall only mildly on one side or the other of this scale—they use components of both sensing and intuition on a regular basis.

Judging: Thinking/Feeling

What do you do once you’ve perceived the world around you? You take action. (Or go watch TV, but let’s stick with the former.) This scale examines how you decide what action to take: logical analysis or empathy with the situation and people. Here are the characteristics of each:

• The person relying primarily on thought will look at the problem from the outside and reason through the best course of action. They may be a very caring and compassionate person, but their end decision is rooted more in logic than their feelings about the situation.

• The person relying on feeling puts themselves emotionally into situations, relating to people and circumstances on a more personal level. They may have tremendous reasoning horsepower, but they are fundamentally guided by their feeling about the right thing to do.

Programming comes with many straightforward situations where you have to think through a decision. I’m not talking about those situations. It’s the ambiguous ones where this scale is meaningful. For example, you’re working with another programmer to implement a feature, and you and she need to decide who does what.

The thinker’s decision might go like this: we need to break apart the tasks so that each of us has a roughly equal load, we need to parcel out the tasks to the person who has the most expertise in each area, we need to make sure neither of us is stuck waiting on the other…

The feeler’s decision, on the other hand, might go like this: I know she likes to work on database stuff and wants to do more of that, and the managers want to see visible progress on this feature soon because they’re worried we can’t pull it off, so I should rough out the user interface while she’s doing the database part…

In a way, the judging scale is sort of the flip side of perceiving scale: there’s how you see the world and what you do about it. However, the scales are indeed orthogonal: there are people who are sensing/feeling or intuition/thinking.

Programmers most likely fall largely on the thinking side of the scale, simply because we spend all day telling the computer how to make decisions based on data. Surely some of that seeps back into our own thought processes. However, don’t discount the feeler’s method of decision as inferior: in the big picture you’re dealing with humans day in, day out, and some empathy with them will go a long way.

Lifestyle: Perception/judgment

The final scale indicates a preference between a person’s perception mode vs. their judging mode. Obviously, everyone does some mix of perceiving and judging. You can’t judge until you’ve perceived. However, when a situation doesn’t need immediate judgment, does a person like to stay in perception mode or immediately move to judgment mode regardless of need?

• The perception-focused person likes to continue gathering input (either via sensing or intuition) and is OK with the situation staying undecided until a decision really needs to be made. They like to keep their options open, seeing no need to shut off additional opportunities for perception.

• The judgment-focused person likes to make a decision (either via thinking or feeling) and move on. Once they’ve perceived enough of a situation to make the call, leaving the situation open is just a source of stress.

This scale can be tremendously frustrating when two people don’t recognize that they’re on different ends of this preference. Let’s say your manager falls on the judgment side, and you fall on the perception side. Your manager wants a decision on a certain technology to bring into the product. You’d rather keep it open since there’s no immediate need to pick one vs. the other, and more time means more experience with the technologies in question.

Your boss gets frustrated, not understanding where you’re coming from. He may consider you a slacker. He may lay down an artificial deadline. You, in turn, get equally frustrated. You think he’s getting authoritarian. You think he’s rushing a decision.

Really, all that’s going on is a difference on the lifestyle scale. In a perfect world, you’d both recognize your different temperaments and compromise on making a decision timeline that gives you your perception time but still closes the decision before your manager gets overly stressed.

Common Combinations

If you think about the stereotypical programmer, all logic and no heart, you’d think of ISTJ: introverted, sensing, thinking, judgment. In fact, this is the most common combination for men in the United States, with an estimated 14 to 19 percent falling in this category.^[38] The second-most common combination is ESTJ—the extroverted guy with all logic and no heart—comprising another 10 to 12 percent of U.S. men.

The women aren’t dramatically different. ISFJ is most common with 15 to 20 percent, replacing the guy’s thinking manner of judgment with feeling. ESFJ is another 12 to 17 percent. Sensing and judgment are most common across both sexes.

If you fall into one of the common categories, good news—odds are you won’t have much trouble relating to the person next to you. On the other hand, if you’re one of the outliers, recognize that early and understand that you’ll need to put extra emphasis on relating to other personality types. Also, recognize that you may have a unique perspective on things—you may truly be the only person in the room who responds to a situation in the way you do.

Actions

Take the Myers-Briggs Type Indicator assessment. The test needs to be administered by a qualified tester. Your company’s HR department may foot the bill—ask your manager.

See whether any of your friends have taken the MTBI assessment. Take your best guess before they tell you their type—were you right? Some of your friends might surprise you. If so, are there any clues that you should have picked up on? Try to figure out, for example, how to tell an expressive introvert apart from an extrovert.