It's a Jungle in There: How Competition and Cooperation in the Brain Shape the Mind (4 page)

You, too, as an individual perched on a precipice or on some less scary site, make decisions that reflect your collective activity. That this is so can become clear to you introspectively. In midair, having decided to leap, you may feel strangely like a witness to your own resolve. “I’m flying across the ravine,” you may say to yourself in a kind of out-of-body experience. “If I’m aloft, I must have decided to jump.” In this brief avian moment, you may even be reminded of René Descartes’ famous declaration, “I think, therefore I am.” In your case, given where you are at the moment—in midair, flying from one cliff to another—you may say, “I jumped, therefore I decided.”

This is a strange way to make up your mind, of course, but for better or worse it’s how you do so. If you go one way or the other, over the cliff or back from whence you came, you made up your mind. There’s no escaping that conclusion. Still, if you remain undecided in the midst of the action itself, then it feels like what you did was heed the outcome of a referendum rather than enact some clear-headed decision you made like the decisive captain of a ship.

These considerations suggest that it may be illusory to say you’re one coherent being. You’re not. You’re
many
beings. Your mental interior is inhabited by mental gnomes all living in your neural ecosystem. The motto of the United States,
E pluribus unum
(
Out of many one
), applies to you, just as it does to the USA.
¹⁶
You’re a plurality. When you think, you engage in group-think. When you act, you act on behalf of untold numbers of beings within you who function in ways that may or may not happen to ensure their own survival.

This view of yourself as a population made up of beings, none as intelligent as you but collectively comprising you with no one in charge, is the view of cognition I wish to advance in this book. I hope you, all of you, will find the perspective useful.

Declaring that your mind doesn’t have a head honcho can be scary. It violates your sense of self, your sense that you’re an individual. Seeing yourself as a conglomerate of self-interested imps rather than a clear-headed captain of your own fate can leave you feeling disoriented. Where’s your compass? How do you know which way to go?
¹

If you think it’s scary to fire your own mental guy or gal in charge, think what it must have been like for Charles Darwin, the hero of the story to come, who suggested that no chief executive is needed to explain the formation of species, including the species to which we humans belong,
homo sapiens
, otherwise known as “knowing man.”

You probably know the core of Darwin’s theory, but I’ll review it here to set the stage for what’s to come. I won’t go into details about evolutionary biology. My aim will simply be to lay out Darwin’s theory as a general model for the kind of cognitive theory I wish to propose for mental function.

Charles Darwin was born in 1809 into an affluent British family. His grandfather was Erasmus Darwin, a well-known thinker and physician in his day.
²

Charles didn’t have to work for a living. Blessed as he was with the freedom to contemplate nature without having to sweep chimneys or swab floors, he could ponder at leisure the diverse forms of life he observed as he ambled through the countryside and wandered on the shore. His most famous ambling occurred on the Galapagos Islands, off the coast of Ecuador, which he visited on a voyage around the world aboard a boat called, aptly enough, the
Beagle
.
³

As a child, Darwin learned that God created the heavens and the earth. Darwin learned as well that soon after God created the heavens and the earth, God created all of the earth’s plants and animals. Finally, young Darwin
learned that God created Adam and, from Adam’s rib, God created Eve. God did all this in just a few days, after which God took a one-day sabbatical and then returned to work, doing God-knows-what ever since.
⁴

Darwin would later question the authenticity of the Bible’s Creation story. Doing so took courage, for God is all-mighty. Among God’s abilities are making the sun and stars, parting the seas, forming mountains, and knowing everything that can possibly be known, even while giving people the freedom to think for themselves.

Charles Darwin was raised in a politically progressive Christian (Unitarian) family. The book in which he proposed his radical idea is one of the most famous books in the history of science,
On the Origin of Species by Means of Natural Selection
.
⁵

Darwin was vilified for his radical proposal. For example, in a cartoon that appeared in his lifetime, his head was drawn atop a chimpanzee’s body. But as so often happens when an author’s work stirs debate, the arguments about
Origins
drew a great deal of attention to the work being criticized and helped make the book a bestseller.

Darwin’s fame lived after him. He was buried in Westminster Abbey, a place where monarchs, great poets, and other famous scientists were interred. Darwin was buried there because, despite the controversy around his work, he was recognized as a truly important thinker, one whose idea could hardly be ignored. Over time, Darwin came to be hailed as one of the most important thinkers in the history of Western civilization—along with such luminaries as Newton (a fellow interree at Westminster Abbey), Karl Marx, Albert Einstein, and Sigmund Freud (none of whom lies there). The book you’re now reading is just one of many that have applied Darwin’s thinking to a domain beyond which Darwin originally intended. High tribute, indeed, to his idea!

What was Darwin’s idea? It was that the species of the earth can be traced to a single, original species and that all the species that have ever been here got here, stayed here, or died off through a process called natural selection.

Natural selection is a simple process. The way it works can be summarized in one sentence:
Species that produce offspring tend to survive
. It doesn’t hurt to state that principle another way as well:
Species that don’t produce offspring tend not to survive
.

“Wait a minute!” you might exclaim. “That can’t be the whole story! I could have thought of that myself!”
Perhaps, but the idea has so suffused our culture that it’s hard to imagine not knowing it, at least if you’re the kind of person who reads books like this one. Being ignorant of Darwin’s idea of natural selection is nearly as unimaginable as not knowing that the earth is round. Because of hindsight bias—the difficulty of recreating what it’s like to not know something you once didn’t know but do now—you may find it incredible that there was ever a time when you or others didn’t have command of Darwin’s concept.
⁶
,
⁷

The elegance of Darwin’s idea is the way the story plays out, coupled with the fact that it relies on a small set of functional mechanisms and assumptions. Those functional mechanisms are three in number. They can be rattled off easily:
replication, variation
, and
selection
. The assumptions that go along with the mechanisms are
sex, death
, and
finite resources
.

Before I describe how these functional mechanisms and assumptions play out to yield the panoply of species, I should explain why I have begun this chapter by intoning God and why, for that matter, this chapter has the title it does:
Darwin and the Boss
. The main reason is that there is an analogy behind what I have written here and what I plan to write about later: Natural selection is to God what the jungle principle is to the mental executive. Let me explain.

The functional mechanisms and background assumptions that Darwin offered are sufficient to explain the origin of species. Saying this another way, you don’t need to invoke a divine guiding figure who designs, creates, and kills off species to explain how species originate within the Darwinian system. By the same token, you don’t need a central executive to explain how thoughts arise or die, how behaviors are chosen or suppressed, or how motives arise and subside. What I mean is that Darwin’s suggestion for the origin of species applies to the origin of mental events and the behaviors they allow. Darwin’s attempt to supplant a theistic account of the origin of the species with a self-organizing account inspires the attempt to supplant an executive-laden theory of mental phenomena with an account that eschews a mental overseer. This is not to deny that some mental processes can be called “executive processes.” That term is used by cognitive psychologists today to refer to volition. But saying that the mind as a whole acts as if someone inside directs traffic needn’t imply that there really is such an inner director.

To understand this more fully, consider the following question: How do the mechanisms and assumptions of Darwin’s theory of natural selection lead to the diversity of life forms we see? In particular, how can the observed
diversity of life forms be explained without appealing to a divine being who runs the show?

A way to answer this question is to consider an imaginary world that has just one animal and just one plant. Fortunately for the plant, the animal exhales carbon dioxide. Fortunately for the animal, the plant exhales oxygen. Also, luckily for the plant, the animal poops near the plant, so the plant, through its roots, ingests essential nutrients. And happily for the animal, the plant has lots of yummy leaves that the animal likes to eat.

At first, this looks like a happy scenario. The plant and animal could go on like this for a long time—forever, perhaps, in a happily-ever-after scenario. But as in fairy tales, where the characters are supposed to live on forever but you know that’s impossible, the happily-ever-after ending for the cohabiting plant and animal is also unlikely to last long. If a strong wind comes along and blows the plant’s leaves off its branches, that’s it for the plant and for the animal too. If the animal gets stuck under a rock or freezes or drowns, that’s curtains for the animal and its leafy friend. The story ends all too suddenly. Life ceases to exist if either of these two living things perishes.

To keep things going, what’s needed is multiplicity. Many plants and animals must be on the scene. That way, nature avoids putting all her eggs in one basket. With many animals, if one of them happens to get pinned beneath a rock or happens to freeze or drown, some other animal may be able to take its place. If there are many plants and one gets plundered by flood or gets blown away by a strong gust of wind, some other plant that’s still rooted in the soil can carry on. Having many plants and animals boosts the chances that life continues. This is
replication
, one of the three functional mechanisms in Darwin’s theory.

Another functional mechanism in Darwin’s scheme is
variation
, otherwise known as diversity. Diversity allows species to be prepared, in effect, for what may happen. If all the members of a species are the same, with exactly the same capacity for lifting themselves out from under fallen rocks, for withstanding cold temperatures, or for escaping floods, then all the members of the species will be equally susceptible to those mishaps. However, if the members of the species happen to differ in their physical or behavioral features, then some of them will be more likely to survive than others.

The term used in Darwin’s theory to refer to survival is
selection
. That’s the third functional mechanism in his model. Selection is vital in natural selection because it provides the means of choosing members of a species that have what it takes over those that don’t. The choosing isn’t divine. There’s no Zeus hurling lightning bolts at creatures whose time, he has decided, has come.
Rather, the process is random. Organisms that happen to have features that enable them to survive tend to generate more offspring than organisms that don’t. The surviving organisms are selected-for. The others, the ones that don’t make it, are “selected out.”

Even well-adapted organisms don’t live forever. Darwin appreciated that it would be bad for organisms to live interminably. Elephants surviving endlessly would pile up. Impalas enjoying immortality would run out of running room. This is because resources are scarce. There are only so many goods to go around—only so many leaves for lunching, so many holes for hiding, and so on. Surviving requires competition for food and shelter, not to mention mates.

Mentioning mates brings up the matter of sex, which is another key part of Darwin’s theory. Why should sex exist? What’s the point of it? The question, I realize, may sound ridiculous. “It feels good!” you may exclaim, not quite sure what planet I live on. Before you focus too much on my hedonics—no worries there, I assure you
—it’s more pertinent to recall the pragmatic, less hedonistic, side of sex: Sex produces offspring. Without sex, there would be no babies, no puppies, no kittens, no cubs.

The feeling-good part of sex is, strictly speaking, not critical to its practice. Still, the hedonic (pleasure) part of sex promotes its continuation in generations to come. People don’t watch X-rated movies because they want to fantasize about wheeling baby strollers. They don’t ogle sex gods or goddesses because they’re contemplating the tax deductions they’ll enjoy by claiming more dependents. Sex, or at least the kind that comes with pleasurable moans and groans, is all about the here-and-now. When you watch Nature TV and see animals copulating, you know they’re not planning for their children’s educations. Instead, they are reveling in the buildup to
oh-that-feels-good
. That feeling, or the drive toward it, impels animals (including humans) to do all the strutting, prancing, dancing, and displaying that constitute courtship.