You Are Not So Smart: Why You Have Too Many Friends on Facebook, Why Your Memory Is Mostly Fiction, and 46 Other Ways You're Deluding Yourself (17 page)

When you return to a place where snakes slither underfoot and food grows on bushes, your attention collapses to what is within reach. Your risk instincts serve you well when you are back in the same conditions your brain was evolved to deal with, like if you’re lost in the woods while hiking or hunting. In any circumstance where the only concerns are those of immediate risk and reward, the software handed down through your genes can get you pretty far. Fast-forward to typical human life today, and now your ancient mind must deal with a world mostly out of reach. Loans and retirement plans, heart disease and elections are far less tangible than the growling of your belly and the creatures that slink through the night. Your risk-avoidance systems are great when the situation is concrete but are pretty crappy when dealing with abstraction.

Antoine Becharo and Hanna Demasio in 1997 published a study in the journal
Science
that is often cited as a great demonstration of the unconscious you. They hypothesized your reasoning “is preceded by a nonconscious biasing step that uses neural systems other than those that support declarative knowledge.” In other words, you are problem-solving before you are aware of it.

In the study, participants played a card game without any idea of what the rules were. They knew only they would earn money when they won and lose money when they lost. To play, they drew cards one at a time off the top of four separate decks until the psychologists said they were finished. The first two decks paid handsomely but were loaded with losing cards that took a lot of money away from the subjects. The other two decks paid meagerly, but the losing card’s fees were small. Over time, the people playing would shift from the high-reward but high-risk decks to the low-reward, low-risk ones. The powers of pattern recognition shaped their behavior toward the best choices without their knowing exactly what they were doing. As fascinating as this is, the study goes further. The participants were hooked up to sensors that measured the moisture levels of their skin, a facet of the human body automatically and unconsciously mind-controlled by the sympathetic nervous system. Those levels began to spike as the people reached for the high-risk decks well before they stopped picking those cards. The unconscious was noticing the risks and placing warnings in the suggestion box about how to proceed long before the decision-making conscious mind was able to act. Questioned later, about a third of the subjects were unable to explain why they decided to stick to the safe cards.

Decisions about risk and reward begin with the unconscious you. Unconscious-you notices things are either bad or good, dangerous or safe, before conscious-you can put those feelings into words. Good things reward you, bad things harm you. When you are determining if something is good, you are saying it is worth the risk of obtaining it. Would you sleep overnight with a poisonous snake loose in your apartment? The risk of being bitten in your sleep greatly outweighs the reward of sleeping in your own bed, so probably not. Would you fly to Las Vegas for a vacation? The risk of dying in a plane crash is worth the reward of seeing Penn & Teller and gambling in the desert, so you buy a ticket and deal with the turbulence.

These calculations aren’t done on a blackboard in your mind; they are derived from consultation with gut feelings, emotional twinges rising like the tips of icebergs from the inky depths of your unconscious. Your species, all species, have been making decisions from the gut for far longer than from careful contemplation, so the influence of these mental machinations is great.

In 1982, a patient known to neuroscience as Elliot developed a brain tumor in his orbitofrontal cortex. Although it wrecked his life, it gave to science an unprecedented look into how important emotion is to decision making. Before the tumor, Elliot was a successful accountant with a home, a wife, and savings in the bank. After the tumor, he became unable to make snap decisions and would instead become transfixed when asked to choose something as simple as which shirt to wear in the morning. His emotional brain became unable to communicate with his rational brain after his tumor was removed. When researchers hooked him up to the same sort of skin conductance measurement devices used in the card game stud, he registered no emotional response to photos of mangled bodies or other images normal people instantly recoil from. To him, the images were neither good nor bad. He became a being of pure rational thought, seeing every bit of information flowing into his mind with cold logic. Elliot could no longer make simple choices because he had no emotions. If he had to pick something to eat from a menu, he would endlessly pore over all the variables as if the secrets of the universe were unfolding before him. Texture, size, shape, calories, flavor, the history of his diet, the price—all of these variables and hundreds more would be subdivided into more variables and then weighed against one another in an endless cycle of computation. Without emotion, it became incredibly difficult to settle on any one option. He became a robot without hate, love, or yearning. He eventually divorced, lost his job, money, house, and everything else from his former life except the love of his parents, who took him in.

The affect heuristic, therefore, is often a good thing. You need it to see danger and pick a place to eat after a concert. The problems arise when you must evaluate large numbers or percentages, when you must see connections and abstractions. This is why politicians who bring out charts and graphs tend to fail, and those who use anecdotes tend to win. Stories make sense on an emotional level, so anything that conjures fear, empathy, or pride will trump confusing statistics. It causes you to buy a security system for your house but neglect to purchase radon detectors. It makes you carry pepper spray while you clog your arteries with burritos. It installs metal detectors in schools but leaves french fries on the menu. It creates vegetarian smokers. Well-known, primal dangers are easy to see, easy to guard against, even when greater dangers loom. The affect heuristic speaks to your basic sensibilities about risk and reward while neglecting the big picture and the dangers of complex systems that require study and deeper understanding.

In 2000, Melissa L. Funicane, Ali Alhakami, Paul Slovic, and Stephen M. Johnson had subjects rate both how risky and how beneficial they felt natural gas, food preservatives, and nuclear power plants were on a scale of one to ten. The subjects were divided into groups where some people read only about the risks while others read about the benefits, and then each had to come up with revised ratings. As you might expect, people who read about the benefits later rated the technologies as being even more beneficial to society than they did at first. The weird part? They rated the risks as being lower. The gap widened. The same was true for the other group who rated the dangers as being more risky than they had in the first questionnaire and the benefits as less appealing. They were even more likely to widen the gap when given a short time limit to give an answer. Logically, risks and benefits are two different things and must be judged separately, but you don’t judge things logically. The more something seems to benefit you, the less risky it seems overall. When you see something as good, the bad qualities are played down. When you see something as risky, the harder it becomes to notice the benefits. The affect heuristic is stronger still when something is familiar or speaks to the primal brain.

The feeling you get in your gut telling you yes or no, good or bad is greatly influenced by the affect heuristic. Keep this in mind when you notice fearful language and imagery coming from any source with an agenda. Remember your tendency to rush to judgment and stick with first impressions when someone is obviously playing up the positive side of an issue or begins to use euphemistic language. You are always looking for risks and rewards, but when you want to believe something is good you will unconsciously turn down the volume on the bad qualities, and vice versa. Any familiar danger will overshadow new threats, and first impressions are difficult to change.

Think of a cup completely filled with water. You try to add one drop to this cup, and one drop spills out. You try to pour a cup of water into it, and a cup of water spills out. This is called a zero-sum system. To add anything to it you must remove an equal proportion.

The bank of names and faces and relationships in your mind, the one you use to keep up with who is a friend, who is a foe, and who is a potential mate—this bank is a zero-sum system too. The reason for this doesn’t really have to do with how much space you have to keep the information, it has to do with how much energy you have on tap to devote to worrying about your place in your social world.

In other primates, social relationships are maintained by grooming—picking bugs off of one another. You don’t go to a
Mad Men
party and dig around in your friend’s hair while watching the show. But getting together for any reason is still a grooming behavior. You hang out, work on projects, and talk on the phone to keep connected. Visiting friends just to shoot the shit is the human equivalent of picking ticks off of one another’s backs. As technology has allowed you to be farther and farther apart yet still keep in touch with loved ones, your grooming behavior has remained constant. In fact, most of your innate gregariousness works as it always has by adapting to the norms of the era. In modern life, human relationships are no longer separated geographically. You can probably start with any one person alive and play six degrees of separation to get to any other person. Modern humans are deeply interconnected.

But you can’t keep up with all those people and their connections, not in a real social way—you are not so smart. The truth is, out of this cluster of humans you can reliably manage to keep up with only around 150 people. More specifically, it’s between 150 and 230. Giant cities full of other humans, Internet social networks with hundreds of people sharing status updates, corporations with branches around the world—your brain is incapable of handling the multitude of human contacts populating these examples. All those personalities and quirks, the history of your interactions with each, it becomes a giant file of social information that takes constant maintenance. Psychology has shown us the brain is not like a hard drive, so the problem with too many relationships isn’t a space issue. The problem is more about the economic limits of your mental human relations department.

Why is this?

The neocortex of primates is the part of the brain responsible for keeping up with others. We can’t be certain of what forces shaped the size of this part of the brain, but for each primate the size of the cortex correlates with the size of the average social group. Apes live in small groups; humans live in big ones. Robin Dunbar, the anthropologist who first presented this concept, figures the size of the average group is directly correlated with how efficiently the members can socially groom one another. Dunbar says that efficiency is predicted by how large the primate’s neocortex is. According to Dunbar, the larger the group, the more time must be spent by each member to maintain social cohesion. Each person must do some grooming with each other person and then also keep up with who is friends with whom, who has a beef, and what each other’s relative status is compared to his or hers and others’. The complexity builds exponentially with each new member. If someone you know moves away, you start to groom that person less and less, until you start to touch base once a year, or maybe lose touch for years. It takes far more effort to stay connected once a friend escapes your direct contact. That effort takes away from the time you can spend with other friends. Your brain was shaped in a world where this time also took away from other efforts—like hunting, gathering, and building shelter. There is a maximum amount of time and effort you can spend—it is a zero-sum system.

Since efficiency is the predictor of group size, you have an advantage over apes and monkeys in the form of language. Social grooming through language is more efficient than grooming through picking lice and fleas, Dunbar says. The preset amount of effort afforded you by your neocortex sets the limit on group size. To add more people to a group would ruin the cohesion. An unbalanced group fails. A balanced group succeeds.

This upper limit shaped the way humans have organized throughout history.

Sure enough, all the sciences that study tribes, bands, and villages have approximated ancient groups usually maxed out around 150 people. This is the approximate upper limit to how many people you can trust and count on for favors, whom you can call up and have a conversation with. Once you go over 150 people, Dunbar says about 42 percent of the group’s time would have to be spent worrying about one another’s relationships. It would take a lot of pressure from the environment for it to be worth growing a group to that level. Once people started coming up with ways to maintain larger groups, like armies, cities, and nations, humans started subdividing those groups. Dunbar’s number explains why big groups are made of smaller, more manageable groups like companies, platoons, and squads—or branches, divisions, departments, and committees. No human institution can efficiently function above 150 members without hierarchies, ranks, roles, and divisions.

In the wild, it takes a lot of work to get a group of 150 people to cooperate and pursue a common goal. In modern life, you depend on institutional structure. As Malcolm Gladwell pointed out in his book
The Tipping Point,
if a company grows beyond 150 people, productivity sharply declines until the company divides its outlying entities into smaller groups. You function better in a cluster—that way everyone in that cluster is connected to one another and only certain individuals connect your cluster to other clusters.