2001 presidential address a brief history of human society ... · ever, early hominids lived in...

THE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETYTHE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETYTHE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETYTHE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETYTHE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETY 11111

American Sociological Review, 2002, Vol. 67 (February:1–29) 1

guaranteeing that humanity’s future will un-fold there. Shortly thereafter, surely duringthe second decade of the century, the lasthunter-gathers will cease to exist, ending 6million years of dedication to what Diamond(1992:191) called “the most successful andlong-persistent lifestyle in the career of ourspecies.” Sociology should be well-poised tounderstand the nature and meaning of theseincredible transitions; but I believe it is not,owing to three interrelated conceits.

The first is our elevation of the social overthe biological. Somehow we have allowedthe fact that we are social beings to obscurethe biological foundations upon which ourbehavior ultimately rests. Most sociologistsare woefully ignorant of even the most el-ementary precepts of biological science. Ifwe think about biology at all, it is usually interms of discredited eugenic arguments andcrude evolutionary theorizing long since dis-carded in the natural sciences.

Direct correspondence to Douglas S. Massey,Department of Sociology, University of Pennsyl-vania, 3718 Locust Walk, Philadelphia, PA19104-6299 ([email protected]). The au-thor thanks Mary Fischer and Sid Seale for theirassistance in preparing the graphics for thisarticle.

Douglas S. Massey

University of Pennsylvania

Human society emerged over 6 million years of hominidevolution. During this time group size steadily increased,and to maintain group cohesion human beings gradually

evolved a well-developed social intelligence based on thedifferentiation and refinement of emotions. The neurologi-cal structures for emotional expression are part of theprimitive brain and developed long before the cognitive

equipment for rational intelligence evolved. Indeed, full rationality came rather latein human evolution, and it has only been within the last 100 years that the social

conditions emerged for a mass culture based on rationality. A review of the evolutionof human society and human cognition illustrates the creation and workings of thehuman emotional brain and show how it operates independently of and stronglyinfluences the rational brain. If sociology is to advance, research and theory mustgrapple with both rational and emotional intelligence and focus particularly on theinterplay between them.

arly in the twenty-first century,two momentous events will occur.

Somewhere around 2007 humanity willcross a demographic Rubicon: For the firsttime, more than half of all human beings willlive in cities. From that point on, the bulk ofpopulation growth will occur in urban areas,

E

A Brief History of Human Society:

The Origin and Role of Emotion

in Social Life

2001 PRESIDENTIAL ADDRESS

“ As you know, sir, in the heat of action menare likely to forget where their best interestslie and let their emotions carry them away.”

Sydney Greenstreet in“The Maltese Falcon”

Written and directed by John Huston

22222 AMERICAN SOCIOLOGICAL REVIEWAMERICAN SOCIOLOGICAL REVIEWAMERICAN SOCIOLOGICAL REVIEWAMERICAN SOCIOLOGICAL REVIEWAMERICAN SOCIOLOGICAL REVIEW

The second conceit is our focus on the“modern” rather than the “traditional.” So-ciology came of age in the late nineteenthcentury as an attempt to comprehend newsocial forms arising out of urban industrial-ism, leaving the study of so-called “primi-tive societies” to our colleagues in anthro-pology. But a science of human society is ascience of human society, and as such itshould span all communities, from smallbands of hunter-gatherers to large urban ag-glomerations. I can think of no more obvi-ous relic of nineteenth-century colonialistthinking than the continuing division be-tween anthropology and sociology.

Finally, sociologists have unwisely el-evated the rational over the emotional in at-tempting to understand and explain humanbehavior. It’s not that human beings are notrational—we are. The point is that we arenot only rational. What makes us human isthe addition of a rational mind to a preexist-ing emotional base. Sociology’s focusshould be on the interplay between rational-ity and emotionality, not on theorizing theformer while ignoring the latter or posingone as the opposite of the other. Attemptingto understand human behavior as the out-come of rational cognition alone is not onlyincorrect—it leads to fundamental misunder-standings of the human condition.

In this address I seek to explicate and am-plify these three critiques by undertaking abrief review of human society from its ori-gins to the present. I date the origins of hu-manity from the point at which we began towalk upright, which freed our hands for themanufacture of tools and our brains for ab-stract thought. In tracing our origins fromthe remote past to the present, I seek to illu-minate what sort of beings we really are, andto project how we might be expected tofunction in the dense, urban environments ofthe future.

THE PATH TO THE PRESENT

We are the survivors of a host of bipedal pri-mates, known as hominids, who oncewalked the earth. The path of descent fromthe first biped to ourselves resembles not somuch a tree as a shrub, with many branchesdrifting off to extinction and others extend-ing toward the present. Considering this

shrub from its origins to the present and pay-ing attention to the fundamentals of popula-tion, community, technology, subsistence,and culture, I identify seven basic eras ofsocietal development.

Prehabiline Society

Recent archaeological finds have pushed theorigins of the hominid line back to 6 millionyears ago, when Ardepithecus ramidus andlater Australopithecus africanus descendedfrom the trees to spend their days walkingupright on the ground, which enabled themto exploit an emerging ecology of mixed for-est and grassland (Wrangham 2001). Ourearliest ancestors were small, averaging 1.5meters in height and maybe 70 kilograms inweight, but they exhibited a pronouncedsexual dimorphism that left males 60 percentlarger than females. Among primates, suchdimorphism is associated with a pattern offemale out-marriage into a group composedof a dominant male plus subordinates, con-sorting females, offspring, parents, and sib-lings (Goodall 1986, 1990). As such, dailylife was probably similar to that of modern-day chimpanzees, which is organized aroundforaging, scavenging, and the occasionalhunting of small prey (de Waal 1998;Dunbar 1988; Goodall 1986, 1999).

There is no evidence that the early Aus-tralopithecines manufactured permanenttools—hence their society is labeled pre-habiline. Like modern chimps, they prob-ably modified perishable materials to use astools (such as sticks to fish termites or leavesto soak up water), and they may havewielded unworked stones for a variety ofpurposes. The teeth of the Australopith-ecines were large, their jaws were adaptedfor crushing, and their guts were capacious,suggesting a diet centered on vegetable mat-ter. Some have argued that the Australopith-ecines descended from the trees precisely toexploit new, ground-based food sources(protein-rich roots and tubers) that were be-coming available on the expandingsavannahs (Wrangham 2001).

Groups of early hominids, like modernchimps, were probably loosely structuredsocially (Maryanski and Turner 1992; Turner2000). Chimpanzee communities are heldtogether by emotional bonds between indi-


viduals differentiated by sex, age, and rankin a dominance hierarchy. Within groupsrather strong ties exist between mothers andchildren, and these ties may persist even af-ter the children are grown, especially formale offspring. Weaker ties exist betweenadult males, and ties between other commu-nity members are generally weak or absent.Females transfer out to join other groups atpuberty, preventing the formation of strongstructures based on intergenerational matri-lines of related females and male dominancehierarchies. Among apes—and among ourlast common ancestors—social structure isfluid, “leaving individuals at the micro levelto seek out their own supportive ‘friend-ships’ that reflect personal likes and dis-likes,” which creates an overall sense ofcommunity at the macro level (Turner2000:9).

Emotional bonds of kinship and friendshipare maintained by mutual grooming, whilerank is established by threat displays occa-sionally backed up by force. Social relationsare complex, requiring each individual torecognize and form alliances with others.Chimps must cultivate webs of influence andmutual obligation, form coalitions to defeatcommon adversaries, remember the personalattributes and past behaviors of others, andknow of relationships between others (Byrne1995, 2001; de Waal 1998, 2001; Goodall1999). Studies and field observations showthat chimpanzees are self-aware and able to

infer the intentions of others and fully ca-pable of social deception and manipulation(de Waal 1998, 2001; Gallup 1970, 1982;Goodall 1986, 1999; Yerkes [1943] 1988). Itis quite likely that Australopithecines pos-sessed similar capacities (Maryanski 1987,1992,1993).

Compared with modern-day chimps, how-ever, early hominids lived in larger groups.Whereas Chimps normally exist in groups ofabout 50, calculations by Dunbar (1996)suggest that Australopithecines lived inbands of 60 to 70 individuals. Like chimpan-zees, therefore, the earliest hominid speciesmust have possessed a well developed socialintelligence. The number of possible dyadsamong any N individuals is given by the for-mula (N2 – N)/ 2, which is graphed as afunction of group size in Figure 1. Whereaschimps (at N = 50) must keep track of 1,225dyadic relationships, Australopithicines (atN = 65) had to manage 2,080, which requiresgreater cognitive ability (Dunbar 2001). Asa result, the average cranial capacity of Aus-tralopithecines, about 450 cc, was largerthan that of chimps, which averages about400 cc (Napier and Napier 1985).

The increase in cranial capacity reflects anexpansion of the neocortex, the outermostlayer of the brain, yielding a higher degreeof encephalization (Jerison 1973; Passing-ham and Ettlinger 1974). Despite their keensocial intelligence, however, there is no evi-dence Australopithecines possessed much in

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Homo habilus: N = 75; dyads = 2,775

Homo erectus: N = 110; dyads = 6,000

Homo neanderthalensis: N = 140; dyads = 9,730

Figure 1. Number of Dyadic Relationships Graphed by Group Size

Note: The number of dyads is a function of group size. It is determined by the formula (N2– N )/ 2.


the way of what we would call rationality.The frontal, temporal, and parietal lobes ofthe brain—the loci of abstract reasoning andlanguage—remained relatively undeveloped,and there is little evidence of any asymme-try between the right and left hemispheres, adefinitive characteristic of hominids whomanufacture tools. Expansion of the neocor-tex occurred mainly in those portions thatdealt with sensory processing and probablyinvolved a “rewiring” to enable greater cor-tical control of emotional expression (Turner1997, 2000).

Like modern chimps, the early Australop-ithecines could probably solve simple prac-tical problems and learn through observationand imitation, but communication was re-stricted to simple vocalizations and gestures.Although modern chimps can be taught 150to 200 symbols in the laboratory and canlearn to string them together in sets of twoor three (Snowdon 2001), they display noawareness of word order (syntax), and overmillions of years they have never used sym-bols on their own (Lenneberg 1980). Chimpsdo not even engage in spontaneous pointing,a behavior displayed by the youngest humanchildren (Bruner 1986).

Prehabiline cognition is associated withwhat Donald (1991) calls episodic culture,in which perceptions and behaviors flowlargely in the present moment. Individualshave memories of concrete past episodes,they can recall prior experiences, and theycan perceive ongoing social situations; butthey lack semantic memory and abstract rea-soning. Prehabiline society and its episodicculture dominated human life for 3.5 millionyears. During all this time—some 175,000generations—no stone tools were produced.Hominid life was confined to Africa andyielded a population that numbered only inthe thousands or tens of thousands of beingsdispersed into small roaming groups (Coale1974). The essential features of prehabilinesociety are summarized in Table 1 and arecompared with succeeding societies.

Oldawan Society

The first revolution in human history oc-curred with the appearance of stone toolsabout 2.5 million years ago and was associ-ated with the appearance of a new genus of

hominids. Homo habilis made crude stoneartifacts that most of us would not even rec-ognize as tools. Named for the East Africangorge where they were first discovered,Oldawan tools are pieces of rock that havebeen sharpened on one side by flaking to cre-ate crude choppers and scrapers. Thesesimple tools are associated with the first evi-dence of patterned human living in the formof centralized butchering sites and indicate agrowing reliance on hunting over gathering.

Although the height of Homo habilis didnot differ dramatically from Australo-pithecus africanus, body weight was largeras their skeletons were more robust, and cra-nial capacity averaged about 550 cc (Stringer1992)—a 20 percent increase associated withan expansion of group size to 70 or 80 indi-viduals (Dunbar 2001). The increase in groupsize was accompanied by a greater cognitivecapacity to monitor the increased number ofinterpersonal dyads (2,775 at N = 75); it alsonecessitated a concomitant increase in theamount of time spent grooming. Primatescultivate and maintain dyadic bonds throughmutual grooming, which causes the releaseof natural opiates in the brain, which in turnpromote feelings of well-being and attractionand lead to social cohesion (Keverne,Martensz, and Tuite 1989). For maximumgroup cohesion to be achieved, every groupmember must groom or be groomed by ev-eryone else.

As a result, group size is naturally limitedby the amount of time individuals can affordto spend grooming each other rather thanengaging in other essential behaviors such assleeping, feeding, courting, and mating(Dunbar 2001). Across primates 20 percentseems to represent an upper threshold fortime spent grooming. The group size char-acteristic of Homo habilis for the first timepushed grooming time above this threshold,suggesting that other social mechanismsmust have come into play to maintain rela-tionships (Aielo and Dunbar 1993). Turner(2000) suggests these mechanisms involveda more complex communication of emotion.

Beyond increased group size, the exist-ence of stone tools, and a larger brain, littleelse changed cognitively, culturally, or so-cially for hominids during the Oldawan pe-riod, which lasted around 1 million years, or50,000 generations. The total human popu-


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lation at the time still numbered only in thetens of thousands, all lived in Africa, andthere is no evidence of any use of languageor symbolic culture (see Table 1). Hominidculture remained episodic, albeit with an in-crease in social complexity and a concomi-tant expansion of cranial capacity to handlegreater demands for social intelligence.

Paleolithic Society

About 1.5 million years ago the appearanceof another species and a new technology sig-naled the emergence of a new kind of soci-ety. The species was Homo erectus and thetechnology was the Acheulean tool culture(named for French village, Saint Acheul,where the tools were first found). The pro-gression from habilis to erectus marked anabrupt and very important shift in humanevolution (Donald 1991). Although the up-per heights of the two species differed rela-tively little, the size of Homo erectus becameconsiderably more uniform (1.3 to 1.5meters)—sexual dimorphism was reduceddramatically from a 60-percent male/femaledifferential to one on the order of 15 percent,about the average for modern humans. Ana-tomically, full shoulder rotation disappeared(which is why modern humans cannot bra-chiate well), indicating a final break fromarboreal life. Both teeth and guts grewsmaller, suggesting the increased nutritionalimportance of meat. And with the emergenceof Homo erectus we find evidence of the con-trolled use of fire (Brain 1983) and the cre-ation of seasonal base camps (Donald 1991),suggesting the emergence of a nomadic life.

The sharp decrease in sexual dimorphismstemmed not from a reduction in the size ofmales, but from an increase in the size of fe-males, thus raising the average height ofhominids. The increase in the size of femaleswas necessary to accommodate the birth ofthese new creatures with large heads and fatbrains, as the progression from Homo habilisto Homo erectus was accompanied by a dou-bling of cranial capacity—from about 550 ccto 1,000 cc to 1,100 cc. The dome of the cra-nium rose, and the face flattened to accom-modate expansion of the frontal, temporal,and parietal lobes of the brain. Homo erectusalso provides the first evidence of brain lat-erality—a differentiation in size between

right and left brain hemispheres—which isassociated with handedness and communica-tive abilities (Donald 1991). Rather than thecrude stone choppers of the Oldawan cul-ture, the Acheulean tool kit evinced consid-erable manual dexterity (which goes alongwith handedness). Tools now consist of sym-metrically shaped, carefully worked handaxes, cleavers, and knives with sharper andmore effective cutting surfaces.

The decline in sexual dimorphism and theneed to care for large-brained children whowere helpless in infancy, vulnerable in child-hood, and dependent through adolescenceproduced a radical change in human socialstructure and mating patterns (Ellison 2001).It was probably during this era that the hu-man practice of pair bonding appeared, ac-companied by a decline in intermale con-flict, the disappearance of rigid dominancehierarchies, and a growing investment by fa-thers of their time and resources for the ben-efit of their mates and children (Lovejoy1980). Male commitment to pair bondingwas reinforced (though not guaranteed) byan entirely new reproductive biology, inwhich females were continuously sexuallyreceptive, breasts were enlarged and dis-played, and the timing of estrous was hid-den. The distinctively human and unprimate-like practice of copulating in private prob-ably also emerged at this time.

Homo erectus’s increased brain size en-abled another expansion in group size, to 90to 120 individuals, yielding somewhere inthe neighborhood of 6,000 dyadic relation-ships (N = 110). Despite greater encephal-ization, however, evidence suggests that theintelligence of Homo erectus was still pre-linguistic. It was, however, different fromthe episodic intelligence that preceded it.The basic cognitive function for Homoerectus was mimesis—imitation or mim-icry—in which vocalizations, facial expres-sions, eye movements, body postures, andmanual signs were used to communicate andto transmit skills from person to person.

The emergence of gestural communicationreflected a significant increase in the rangeand complexity of emotional expression, asthe cognitive bases for primary emotionssuch as fear, anger, disgust, happiness, andsadness were rewired and interconnected viathe cortex to produce new sets of emotions


conducive to social cohesion and solidarity,such as shame, guilt, anticipation, and hope(Turner 2000).

Learned physical skills among Homoerectus were an essential adaptive resourceand were passed from generation to genera-tion by demonstration and imitation (Donald1991). Although mimetic culture remainedconcrete, visual, and episode-bound, it nev-ertheless brought about an increase in thesharing and accumulation of knowledge,yielding a more stable social structure basedon ritual and custom, which served toheighten the emotional content of social re-lationships and promote bonding (Turner2000). It was probably during this phase ofhuman social evolution that facial expres-sions attained their current importance as ameans of signaling emotion. Patterns of non-verbal facial expression recur across culturesand are interpreted similarly by humans inall societies, suggesting a “hard wired” abil-ity to read emotions that are displayed on thehuman face (Eibl-Eibesfeldt 1989; Ekmanand Rosenberg 1997; Goleman 1995). Theresulting mimetic culture provided humanswith a powerful adaptive tool that enabledthem to leave their ancestral homeland forthe first time and survive in a wider varietyof habitats. Around 1 million years ago,Homo erectus moved out of Africa and oc-cupied the southern portions of Asia and Eu-rope, a move which brought about the firstsignificant growth of the human population(Coale 1974).

Late in the paleolithic period, around300,000 years ago, several new species ofhominid arrived on the scene to competewith Homo erectus, who eventually disap-peared. The new species were Homoheidelbergensis and the better-known Homoneanderthalensis, also known as the Nean-derthals (Tattersall 1995). The latter ap-proximated modern humans in height, butwere much heavier and more powerfullybuilt, with thicker bones and a more robustmusculature. The size of the Neanderthalcranium also expanded to reach volumescharacteristic of our own species, althoughthe physical organization of the brain re-mained distinct, with small and constrictedfrontal lobes. Nonetheless, the increase inaverage cranial capacity to around 1400 ccenabled group size to expand further, reach-

ing 120 to 160 individuals and implying aneed to manage some 9,730 separate dyadicrelationships (N = 140; see Figure 1)

With groups this large, the maintenance ofcohesion could not possibly have relied onmutual grooming, as servicing so many rela-tionships would have required around 40percent of the group’s entire time to be spentgrooming, a percentage that is far too largeto be feasible (Dunbar 2001). Culture, there-fore, must by then have been the centralmechanism maintaining social cohesion.Nonetheless, both the fossil and archaeologi-cal evidence suggest that Neanderthals weremimetic and nonverbal (Diamond 1992;Donald 1991; Tattersall 1995): Their con-stricted frontal lobes and a skull flexure in-capable of accommodating a modern vocalapparatus suggest that Neanderthals couldnot speak (Lieberman 1975, 1984).

The Neanderthals nonetheless evinced amore advanced material culture than theirhominid predecessors, as indicated by theemergence of a new tool kit, the Mousterian(again named for a French village), whichconsisted of flint or stone blades hafted ontowood or bone handles. These are the firstcomposite tools—those composed of at leastthree materials. The new tool kit yielded 10times more cutting edge per kilo of raw ma-terial than the former Acheulean technology.With the Neanderthals we also begin to ob-serve stone hearths and postholes, indicatingthe construction of permanent shelters. Wealso observe migration and settlement in thecolder regions of northern Europe, and nu-merous bone middens indicate a heavy reli-ance on hunting for food. With the emer-gence of semipermanent settlements of 120to 160 persons, social structure probably be-gan to move beyond small bands differenti-ated by age and sex to form larger collectivessuch as kin-based clans (Tattersall 1995).

Neolithic Society

Fully modern human beings emerged in Af-rica somewhere around 150,000 years agoand rapidly migrated outward to occupy allcorners of the globe. Homo sapiens reachedEurope and Asia around 50,000 years beforepresent (B.P.), Australia by 40,000 B.P., theArctic by 20,000 B.P., the Americas by10,000 B.P., and most of the islands of


Polynesia by 2,000 B.P. (Balter 2001; Dia-mond 1997; Gibbons 2001a, 2001b).Whereas the Australopithecines and habi-lines had remained in Africa for 5 millionyears without moving, and Homo erectus andthe Neanderthals had not expanded beyondsouthern Europe and Asia over 1 millionyears, within the space of just 50,000 yearsHomo sapiens fully populated the entireearth. Clearly they must have gained accessto some remarkable new survival tools.Given that the maximum density achieved byhunters and gatherers in the richest habitatsis a little under .5 persons per square kilome-ter (Hassan 1981), demographers estimatethat the prehistoric human populationreached roughly 6 million persons (Coale1974; Landers 1992; Livi-Bacci 1992;).

In Homo sapiens, the brain reached itspresent size and structure with a full expan-sion of the frontal lobes that created the po-tential for a new and revolutionary kind ofculture (Knight, Dunbar, and Power 1999;Watts 1999). The importance of the humanbrain as an adaptive organ is indicated by thefact that it constitutes 2 percent of bodyweight but uses 20 percent of the body’s to-tal energy (Donald 1991). Nonetheless, theappearance of anatomically modern humanbeings was not initially accompanied by dra-matic cultural changes.

The crucial period of cultural changeseems to been around 50,000 years ago, inan era that has variously been called “thegreat leap forward” (Diamond 1992), “thecreative revolution” (Tattersall 1998) and“the symbolic revolution” (Chase 1999).From this point onward, human technologyundergoes rapid change that is disconnectedfrom further changes in brain size oranatomy. Whereas earlier technologies pre-vailed for hundreds of thousands or evenmillions of years and only changed with thearrival of a new species, after 50,000 B.P.material culture evolves rapidly and differ-entiates without any corresponding physicalchanges. Human cognitive capacity had ap-parently reached a state of dynamism andflexibility where it could innovate adapta-tions ad infinitum.

In addition to the hafted stone and woodtools characteristic of Mousterian culture,Homo sapiens now began to fashion a hostof new and more delicate tools from bone

and antler, creating hooks, needles, awls,and harpoons. They wove fibers into ropesand clothing; tanned hides for clothing andcoverings; created jewelry and other formsof personal adornment; and built permanentshelters that not only included hearths, butlamps and kilns as well. They inventedspear throwers, bows, and arrows to alloweffective hunting from a distance, thusminimizing risks to personal safety. Late inthe neolithic era, bronze began to replaceflint in tools and weapons, ushering in a“bronze age.”

Perhaps not immediately, but sometimeafter the appearance of Homo sapiens,speech developed and gave human beings acapacious verbal memory and new capacitiesfor cognition and analysis (Gregory 1981).The development of language was enabledby important changes in the size, structure,and function of the brain compared with theNeanderthals. Expansion of an area locatedtoward the bottom of the frontal lobes(Broca’s area) permitted phonology, the mak-ing and controlling of sounds. The develop-ment the temporal lobes (Wernicke’s area)allowed audition, the ability to hear and dif-ferentiate sounds; and expansion of the pari-etal and frontal lobes permitted conceptual-ization, the ability to use and manipulate ar-bitrary sound symbols in meaningful ways—to think of words before uttering them and toorganize them into large units of meaning.All of these expanded brain functions wereconnected into a larger articulatory loop thatfunctioned in a newly coordinated fashion(Carter 1998; Panksepp 1998).

Language emerged not to give humans acapacity for rational or abstract analysis perse—rational thought was more of a by-prod-uct—but to enhance their social intelligenceto enable them to get along in large groups(Dunbar 1996; Maryanski 1996). Languageis the ultimate social arbiter, allowing peopleto maintain interpersonal relationshipsthrough conversation, to monitor the socialinteractions of others through gossip, and toreach collective decisions through discus-sion. In Dunbar’s (2001) words, “humanshave bigger, more complexly organizedgroups than other species simply because wehave a larger onboard computer (the neocor-tex) to allow us to do the calculations neces-sary to keep track of and manipulate the


ever-changing world of social relationshipsin which we live” (p. 181).

Language is far more efficient thangrooming as a means of maintaining socialcontact and monitoring interpersonal rela-tionships, for the simple reason that we cantalk to more than one person at a time. Themaximum group size predicted for humanbeings from their cranial capacity is around155 persons, which corresponds closely tothe maximum size observed among hunter-gatherer societies (Dunbar 1996). Compar-ing the group size of chimps to that of hu-mans (55 to 155) suggests that the mecha-nism that replaced grooming as a means ofachieving group cohesion was three timesmore efficient. Unobtrusive studies of con-versations conducted across a variety of cul-tural and social settings reveal that humanconversational groups naturally gravitate to-ward a configuration of one speaker andthree listeners. Moreover, whereas chimpsspend about 20 percent of their time groom-ing, humans spend around 20 percent oftheir time in social interaction, mostly inconversation (Dunbar 2001:190–91). Thuslanguage replaced grooming and built upongesture as a means of ensuring social cohe-sion within large groups.

All human societies possess a spoken lan-guage and all human beings are capable oflearning any linguistic system. Indeed, asChomsky (1975) and Pinker (1993) suggest,human beings possess a “language instinct.”Given appropriate exposure in childhood,any person anywhere can learn any languagewith a minimum of effort and without for-mal instruction. In contrast, as stated earliereven after intensive training throughoutchildhood, Chimpanzees cannot learn tospeak any language. And even though theycan learn to recognize 150 to 200 symbols,they cannot use them in grammatical fash-ion (Diamond 1992; Donald 1991).

Despite its evolution as an instrument of“social intelligence,” however, languagealso offered humans new possibilities for ra-tional analysis. Through vocabulary, syntax,and grammar, languages inevitably createdcategories of perception for time, objects,and events in the real world. Languages thusallow humans to create a conceptual modelof the universe and how it works, permittingthe invention of what Gregory (1981) calls

“mind tools”: categories of thought that fa-cilitate other mental operations. The emer-gence of language is thus associated with theemergence of a new kind of “mythic culture”in which humans developed symbolic meta-phors to explain the operation of the uni-verse.

The appearance of musical instruments,rhythmic devices, lunar calendars, and vari-ous other symbols in the millennia from50,000 B.P. to 10,000 B.P. testifies to thegrowing importance of myth in society. In-terment of the dead with utensils, food prod-ucts, and jewelry indicates a belief in the af-terlife (Donald 1991). The first symbolic artappears in the form of sculptures and cavepaintings, and given the remote location ofmost cave art deep in the interior of inacces-sible caverns, it obviously served some sym-bolic, ceremonial purpose (Tattersall 1998).

Mythic culture, for the first time in his-tory, allowed humans to synthesize discrete,time-bound events and circumstances and toconnect them into a single, coherent narra-tive to explain the world. Mythic culture didnot supplant episodic and mimetic cultures;it was wrapped around them and extended apreexisting emotional infrastructure. Everyhunter-gatherer society thus has an elaboratemythic system that permeates daily life, andthrough the use of verbal and nonverbalsymbols, that system gives meaning to ev-eryday objects, circumstances, and events(Donald 1991). Myth constitutes a “sym-bolic web” that explains how people are sup-posed to behave, why cultural rules must beobeyed, and how they are to be enforced(Chase 2001). God myths, in particular, re-flect a society’s idea of causality: where lifecomes from, what happens to people afterdeath, and what controls events in the world.

When considered comparatively acrosstime and space, hunter-gather societies arefound to share a variety of traits (Barnard2001). They occupy large territories at lowdensities and are characterized by geo-graphic flexibility and a lack of attachmentto fixed settlements. They are unstratified,with few social distinctions except for thosebased on age and sex. Males and females aredistinguished from one another by undertak-ing different productive activities and ritualbehaviors, and adults take care of childrenand the elderly. Most groups possess social

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mechanisms to distribute food and preventthe accumulation of surplus. They employ auniversal classification of people accordingto kinship and have a symbolic structurebased on bipolar opposites (good/bad, male/female, hot/cold, etc.). Their metaphoric nar-ratives associate animal identities with thoseof humans, and much of human action is in-fused with ritual (Collins 1987).

Although possessing a capacity for ratio-nal thought, elements of rational cognitionand culture are not very well developed inmythic cultures. Rather, the new cognitiveapparatus created by words was morestrongly connected to emotional centers ofthe brain through conditioning and learningthat were deliberately reinforced by ritual,ceremony, and spirituality (Collins 1987;Turner 2000). The emergence of culturalforms more strongly connected to rational-ity required something that hunter-gathersnever achieved—a food surplus—and thatonly became possible with the domesticationof plants and animals.

Agrarian Society

The signature characteristic of hunter-gath-erer societies is that, except for the veryyoung and the very old, everyone producesfood: Each day all people must work to en-sure the group’s caloric intake. Until quiterecently, human societies had no specialists,and certainly none devoted to full-time cog-nition. This only became possible between12,000 and 10,000 years ago with the emer-gence of the first settled villages, which, inturn, were rendered feasible by the cultiva-tion of crops and the herding of animals. Forthe first time humans had created a food sur-plus. The accumulation of food in excess ofone-day’s needs enabled a dramatic accel-eration of human population growth, higherpopulation densities, and the existence of anew class of people—albeit a small class—who did not have to produce food for theirown survival (Coale 1974; Livi-Bacci 1992;Sjoberg 1960).

Agriculture, herding, and cities emerged atdifferent times in different places dependingon access to plants and animals that werepotentially domesticable (Diamond 1997);but they first materialized in a geographicarc extending from the eastern Mediterra-

nean upward through Anatolia and downinto the valley of the Tigris and Euphratesrivers. Known as the “Fertile Crescent,” itwas here that the ancient ancestors of sev-eral modern cereal crops and herd animalswere found in foothills adjacent to a flat al-luvial plain whose soil was annually replen-ished and watered by seasonal flooding—theperfect environment for the emergence of in-tensive agriculture. Wheat, barley, and peaswere domesticated in Mesopotamia by10,000 B.P., along with sheep and goats; by6,000 B.P. several fruit-bearing trees andbushes had also been tamed (notably thoseyielding olives and grapes). Agriculture wasindependently invented in China, Meso-america, and perhaps India, and spread toEurope and other locations in Asia and theAmericas through diffusion (Diamond 1997;Sjoberg 1960).

The domestication of plants and animalsset the stage for a new kind of human soci-ety based in cities. The first cities emergedin Mesopotamia around 8,000 years ago,with populations in the 5,000 to 25,000range (Sjoberg 1960). Under a preindustrialtechnology, the amount of food that could beproduced per hectare was limited and the to-tal size of the food surplus was necessarilymeager. While intensive agriculture mayhave permitted cities to exist, they couldn’tbe numerous and only a few people couldlive in them. Prior to the industrial revolu-tion, no more than 5 percent of any societylived in cities and the total population of asingle city never exceeded 1 million (Chan-dler and Fox 1974; United Nations 1980).

With yields per hectare fixed by techno-logical limits, the only means for a city tobecome larger was to gain control of moreland and thereby to commandeer a largersurplus. Mesopotamian cities were limited insize by internecine rivalries and politicalfragmentation. It was not until the Pharaohsconsolidated their control over the NileRiver Valley around 5,000 years ago that cit-ies really began to expand. The first settle-ment to exceed 100,000 inhabitants wasThebes, in Egypt, around 3,400 years ago. Itwas succeeded a thousand years later byBabylon, which surpassed 200,000, and fi-nally by Rome, which during the reign ofCaesar Augustus was the first city to surpass500,000. The 100,000-person threshold was

THE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETYTHE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETYTHE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETYTHE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETYTHE ORIGIN AND ROLE OF EMOTION IN HUMAN SOCIETY 1 11 11 11 11 1

crossed in China 2,600 years ago and inMesoamerica about 2,000 B.P. (Chandlerand Fox 1974).

Wherever it occurred, agrarianism dis-placed hunting and gathering as a way oflife—through direct conquest, demographicabsorption, or ecological marginalization.This victory occurred not because agrarian-ism provided people with less work, betternutrition, and longer lives. On the contrary,the residents of early agrarian societiesworked longer hours, consumed fewer calo-ries, lived in poorer health, and within citiesthey died in larger numbers (Diamond 1997;McNeill 1976). What gave agrarian societ-ies their decided advantage in confrontationswith hunter-gatherers was their demographicweight, which allowed them to possess anadvanced technology, specialized fighters,and deadlier germs.

With the advent of agriculture, the stoneage gave way to the bronze and iron ages—metals replaced flint to create more effectivetools and more lethal weapons. Urban dwell-ers and the agrarian empires they maintainedevinced new instrumental needs, specialiststhought up new tools to satisfy them, tradersobtained the necessary raw materials, arti-sans made them, a political elite controlledtheir distribution, and a religious elite justi-fied their deployment. As a result, in any en-counter urban-led agrarian societies wereable to wield weapons and technologies farsuperior to anything that hunter-gathererscould muster. Agrarian societies also couldspare more people from the necessity of foodproduction to wield these weapons, whichled to the emergence of professional soldiersand the first standing armies. In any compe-tition over land and resources, populationsenumerated in the tens or hundreds of thou-sands held a clear advantage over smallbands numbering in the dozens or hundreds,especially if the former fielded an army ofwell-equipped, well-fed, and well-trainedprofessional fighters.

Finally, the density of preindustrial cities,the lack of sewage facilities, the contamina-tion of drinking water, and the close asso-ciation of humans with animals gave one fi-nal advantage to agrarian-urbanism: germs(Diamond 1997). Until the nineteenth cen-tury, in fact, health conditions in cities weresuch that infectious diseases were endemic,

and life expectancies were short, muchshorter than among peasants in the country-side (McNeill 1976; Preston and Haines1991). In fact, were it not for continuous ru-ral in-migration, preindustrial cities wouldnot have been able to sustain themselves de-mographically. Nevertheless, although deathrates were high and life expectancies short,those urban dwellers who survived either in-herited or acquired an immunity to bacteria,viruses, and other parasites that hunter-gath-erers could never attain, given their low den-sities. As a result, throughout history initialcontacts between hunter-gathers and agrari-anism-urbanism have invariably led to theformer’s decimation through a sudden expo-sure to diseases for which they had no natu-ral immunity (Diamond 1997; McNeill1976; Tierney 2000).

From the rise of the first city-states around10,000 years ago up to the year 1800, agrari-anism was the dominant form of human so-ciety, occupying ever larger portions of theworld’s geography with ever larger popula-tions, both rural and urban. The rough tra-jectory of world population growth is shownin Figure 2, which graphs the estimated sizeof the human population from 600 B.C. to1800 A.D. At the end of the paleolithic era,the world’s population stood at around 8 mil-lion; but over the next 8,000 years it grew toreach about 252 million in the year zero.Under the Pax Romana, population growthreached a plateau and with the collapse ofthe Roman Empire it declined to around 200million before rebounding slowly after theyear 600. Beginning in the year 1000, a va-riety of technological and social innovationscame together to unleash a demographicboom in Europe, which proceeded apace un-til the Black Death struck in the middle1300s (Levine 2001). As the foundations fora global economic order based on mass pro-duction, trade, and investment were estab-lished after 1600 (Braudel 1982; Wallerstein1974), the human population entered an eraof sustained exponential growth that accel-erated until the dawn of the nineteenth cen-tury, when the world’s population stood ataround 954 million (Livi-Bacci 1992).

In the 500 generations preceding 1800, theproportion of people living in urban areasnever exceeded 5 percent (United Nations1980), and before that year only 65 cities in


the entire history of the world had everachieved populations greater than 100,000(Chandler and Fox 1974). The vast majorityof people in the “civilized” agrarian societ-ies of the past were illiterate peasants wholived in small villages and isolated hamletsnot much bigger than the hunting and gather-ing communities of the paleolithic era. Workwas governed by the rhythms of the seasons,and most people lived and died within a fewkilometers of where they were born, spend-ing all their lives within a community offriends and relatives they knew personally.In such a society, culture remained substan-tially mythic. The only real difference com-pared with the mythic cultures of hunter-gathers was the patina of formal structureimposed from above by a priestly class.

Through the innovation of written lan-guage, however, agrarianism created thefoundation for a new kind of culture. Theorigins of writing lay in the desire ofSumerian merchants for an accounting sys-tem to keep track of their sales and ship-ments. Some 10,000 years ago, urban trad-ers began using a stylus to mark clay tokensof different shapes, thus indicating the quan-tity and nature of goods being shipped orstored (Harris 1986; Lawler 2001). Over themillennia, these clay tokens expanded intotablets, and the markings were elaborateduntil about 5,000 years ago, when they be-came a syllabic script for the Sumerian lan-

guage. Then, about 4,000 years ago thePhoenicians evolved the first phonetic alpha-bet, which later was borrowed and modifiedby the Greeks and eventually the Romans,whose system we use today (Diamond1997). Writing emerged independently inChina and Mesoamerica at later dates.

The advent of writing created the first ex-ternal memory devices—tablets, scrolls, andstone monuments—which dramatically re-duced the demand on biological memory andfreed up human cognition for other tasks.Whereas biological memory is inherentlylimited by a fixed number of neurons (notall of which we use), writing created a stor-age system of unlimited size. Moreover,through both written and oral connectionsbetween individual brains within dense ur-ban environments, cities dramatically in-creased the size of the human cognitive ap-paratus (Wright 2000). In many ways, theyfunctioned as macro-social “brains,” and theuse of symbols externalized thought and dra-matically increased information processing(Diamond 1997).

Writing thus created the potential for anew theoretic culture—a logical system ofthought grounded in experience and rational-ity and capable of making accurate predic-tions about events in the natural and socialworlds (Donald 1991). Almost by definition,access to such a culture was limited to thesmall minority of people who were literate

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Figure 2. World Population, 600 B.C. to 1800 A.D.

Sources: Coale (1974); Landers (1992); Livi-Bacci (1992).


and freed from the burdens of food produc-tion, and even among those who could readand write there were two competing modesof thought (Bruner 1986; Snow 1959). Nar-rative thought is basically a written exten-sion of oral culture expressed as literature:plays, poems, stores, novels, operas, and soon. Analytic thought, while dependent onwords, is a rational construction grounded informal systems of argument, taxonomy, andconceptualization. Analytic thought followslogical rules based on induction and deduc-tion and makes frequent use of formal quan-titative measurement. Although theoreticculture gained adherents and influence inhuman affairs during the agrarian era, it nec-essarily remained a minor part of the totalhuman experience, given the small numberof people who were literate.

Industrial Society

Agrarian food surpluses allowed a smallnumber of people to devote their time tothinking and innovating, and even though thepercentage of such people remained tiny, thesteady increase in population from Romantimes to 1800 meant that the absolute num-ber of such people steadily grew. Whereas

no more than 5 percent of the world lived incities during the eras of both CaesarAugustus and Queen Victoria, for Romantimes this implied a population of 13 millionurbanites, while for the Victorian era therewere 48 million city-dwellers. The growingquantity of people with the time and freedomto think new thoughts promoted more andfaster innovation, which caused more popu-lation growth, which increased innovation,and so on.

Beginning around 1800, human societyentered a remarkable new period of demo-graphic growth the likes of which the worldhad never seen. Whereas hunting and gath-ering had been the dominant mode of soci-ety for 6 million years and agrarianism for10,000 years, industrialism flowered andmatured in less than 200 years. From a baseof 954 million people in 1800, the humanpopulation grew to 1.6 billion in 1900, 2.5billion in 1950 and 6.1 billion in 2000. Inthe past 200 years, more people have beenborn than in all previous human generationscombined. Even more remarkable has beenthe shift of the human population from ruralto urban areas.

As can be seen in Figure 3, in 1800 thepercentage urban was still roughly at the up-

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per limit for an agrarian society—about 5percent of total population. Slowly at first,and then accelerating in the late nineteenthand early twentieth centuries, there was amassive geographic shift. In the industrial-izing societies of Europe and North Americathe transition to urbanism was rapid andcomplete by the mid-twentieth century(Brockerhoff 2000; Preston 1979). Althoughdeveloping countries lagged behind, they arenow also rapidly urbanizing, and by 2025the proportion of city-dwellers worldwide isprojected to reach nearly 60 percent.

In this century, not only will a majority ofhuman beings be living in cities, but a grow-ing fraction will reside in extremely largeplaces. Beginning in the mid 1920s, the per-centage of human beings living in cities of 1million or more rose sharply. As world ur-banization passes the 50 percent mark to-ward the end of this decade, the number liv-ing in large metropolises will surpass 20 per-cent; and by the year 2025, one-quarter ofall humanity will live in cities of 1 millionor more. Increasingly, most of these large ur-ban agglomerations will be in the ThirdWorld. Whereas the five largest cities in1900 were London, New York, Paris, Berlin,and Chicago, in 2015 they will be Tokyo,Bombay, Lagos, Dhaka, and Sao Paolo, fol-

lowed by Karachi, Mexico City, New York,Jakarta, and Calcutta (United Nations 1999).

The urbanization of society has been ac-companied by a remarkable acceleration oftechnical, economic, social, and culturalchange. Technologically, inanimate sourcesof power replaced animate sources, as horsesand oxen gave way to wind and water, thento coal and steam, and finally to petroleum,hydroelectricity, nuclear energy, solar, andgeothermal power. Economically, the pro-ductive base of society shifted in rapid suc-cession from agriculture to manufacturing toservices, with each transition accompaniedby a startling increase in the productivity ofland, capital, and labor. The creation of massmarkets yielded economies of scale thatwere accompanied by an unprecedented in-crease in social differentiation and stratifi-cation. As the distance between the top andthe bottom of society grew, the interveningspace was filled with a complex array of in-creasingly variegated social strata. Cultur-ally, gender roles changed, childhood wasextended, fertility levels fell, and survivalrates increased to create a demographicstructure in which the old outnumbered theyoung.

Although the foundations for theoreticculture were laid in the agrarian era, the

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Figure 4. Trends in Literacy, 1800 to 2000

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technical constraints of preindustrial farmingnaturally limited the size of the food surplusand hence the percentage of people whocould live in cities, thus placing an upperlimit on literacy. As long as literacy re-mained the prerogative of a small minorityof people who were liberated from the land,the prevailing cultural mix would beweighted toward the mythic rather than thetheoretical. The full flowering of rationalculture, in other words, awaited the adventof mass literacy.

Figure 4 shows trends in the literacy ofadults from 1800 to 2000 in Europe, theUnited States, and worldwide; data are fromCipolla (1969), Lestage (1982), Graff (1987),and Wagner (1993). In 1800, the vast major-ity of human beings would not have hadmuch access to the fruits of theoretic culture,as 85 percent of the world’s population waspreliterate. Even in Europe, only about 40percent could read and write in 1800, owingmainly to mass illiteracy in the Russian Em-pire. The United States fared better, with lit-eracy rates approaching 60 percent.

In Europe and the world, the degree of lit-eracy changed slowly during the nineteenthcentury. As late as 1900 half of all Europe-ans and two-thirds of the world’s populationstill could not read or write. After 1900,however, the extension of public schoolingin Europe rapidly increased literacy there tolevels above 90 percent. Among nations ofthe Third World, meanwhile, national devel-opment programs began to extend universalschooling, and in the late 1940s world lit-eracy broke the 50 percent barrier. By theyear 2000, three-quarters of the world’spopulation had been given instruction in atleast the fundamentals of reading and writ-ing. Nonetheless, nearly one-quarter of allhumanity remained disenfranchised from thebasic requirement for a rational, theoreticculture.

The Emerging Post-Industrial

Order

Despite the incredibly rapid change since1900, there is evidence of an even greateracceleration beginning around 1980 with themass production of the silicon chip and theconsequent introduction of computers intovirtually all aspects of social and economic

life. In the new economic order, wealth restson the creation of knowledge rather than themanufacture of goods, and status derivesfrom the control and manipulation of infor-mation. Although markets are increasinglyglobal in scale, they are also increasinglyfragmented, being divided into segmentedniches rather than mass populations of con-sumers. Within the global economy, capital,labor, goods, commodities, and informationare increasingly mobile and transnational,yielding a new internationalization of bothproduction and culture (Harvey 1990).

Compared with the roughly 300,000 gen-erations that humans spent as hunter-gather-ers and the 500 generations they spent asagrarians, the 9 generations passed in the in-dustrial era and the 1 generation so far spentin the emerging post-industrial era are a dropin the bucket of time. As organisms, we can-not possibly have adapted to the environ-ment in which we now find ourselves. Fu-ture adaptations will come from institu-tional, technological, and cultural changes,not from physiological adaptation. The na-ture and success of our adaptation will de-pend heavily on what sort of organisms weare—how we think and how we function so-cially.

PAST IS PRESENT

In his play, Requiem for a Nun, WilliamFaulkner noted,“The past is never dead. It’snot even past” (act 1, scene 3). Our brainshave evolved over millions of years as achanging mixture of emotionality and ratio-nality, and each evolutionary step has builtupon what came before. Emotionality clearlypreceded rationality in evolutionary se-quence, and as rationality developed it didnot replace emotionality as a basis for hu-man interaction. Rather, rational abilitieswere gradually added to preexisting and si-multaneously developing emotional capaci-ties. Indeed, the neural anatomy essential forfull rationality—the prefrontal cortex—is avery recent evolutionary innovation, emerg-ing only in the last 150,000 years of a 6-mil-lion-year existence, representing only about2.5 percent of humanity’s total time on earth.To the extent we possess rational cognition,it necessarily rests on a preexisting emo-tional foundation.


This evolutionary history is reflected inthe basic structure of our brains, which issummarized in Figure 5. Natural selection isconservative: It doesn’t build new capacitiesfrom scratch, but acts upon structures andfunctions that already exist. As a result, hu-man beings have come to possess whatMacLean (1973, 1990) has labeled a “triunebrain”: three different layers of neuralanatomy laid down on top of one anotherduring different phases of evolution. Theoldest and deepest layer consists of the brainstem and the cerebellum (basal ganglia);these structures control autonomic functions,such as heartbeat and breathing, as well asinstinctual behaviors, such as the sucking re-flex. It is known as the reptilian brain be-cause it closely resembles the structure andorganization of the neural anatomy found inreptiles today, and presumably in the past.

The next layer is called the mammalianbrain (Panksepp 1998). It surrounds the rep-tilian brain and consists of a set of neuralstructures collectively known as the limbicsystem. The most important organ in thissystem is the amygdala, which is crucial inregistering incoming emotional stimuli andstoring emotional memories. Other limbicsystem organs include the thalamus, whichreceives stimuli and relays them to otherparts of the brain; the hypothalamus, whichworks with the pituitary gland to keep the

body chemically regulated and attuned to itsenvironment; the hippocampus, which is re-sponsible for laying down memory; and asurrounding layer of tissue known as the cin-gulate cortex. Together these cerebral organswork together unconsciously to coordinateinputs from the senses and to generate sub-jective feelings and emotional states that in-fluence subsequent cognition and behavior(for a detailed account of the neurology ofemotion, see Turner 1999, 2000).

The outermost layer of the brain is theneocortex, also known as the neomammalianbrain (Panksepp 1998). This consists of anouter layer of gray matter mostly given overto the conscious processing of sensorystimuli. The neocortex has four basic sectorsreplicated symmetrically across two hemi-spheres of the brain. At the back, the occipi-tal lobes do visual processing. Along the topand sides, the parietal lobes focus on move-ment, orientation, and calculation. Behindthe ears, the temporal lobes deal with soundand speech; and the lower part of the frontallobes are devoted to taste and smell. The toppart of the frontal lobes is known as the pre-frontal cortex.

The foregoing organization is common toall mammals, although different lobes maybe more or less developed in different spe-cies. Dogs, for example, have a better senseof smell than humans, and consequently

Neomammalian (neocortex)

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Figure 5. The Triune Structure of the Human Brain


their smell portion of the neocortex is morehighly developed. The feature of brainanatomy that most distinguishes humansfrom other mammals is the relative size ofthe prefrontal cortex. This portion of thebrain mushroomed spectacularly over thecourse of hominid evolution to the pointwhere the prefrontal region now constitutes28 percent of the entire cerebral cortex, 40percent more than in our first hominid an-cestors (Carter 1998).

The prefrontal region is the only portionof the neocortex that is free from the de-mands of sensory processing, and as such itis the locus for abstract thinking, conceptu-alizing, and planning. It is this section of thebrain that is most clearly associated withself-will and human consciousness—theplace where we process and analyze infor-mation about the world and make plans forthe future that are transmitted downward tothe limbic system and basal ganglia alongwell-developed neural pathways. If the pre-frontal lobes are damaged, human beings areunable to plan, to motivate themselves, or torecognize and act upon emotions (Goleman1995; LeDoux 1996).

Leaving aside the reptilian brain and itslargely autonomic functions, evolution hasbequeathed us two dynamic, interactivebrains—one emotional brain located in thevarious subsystems of the limbic system,and one rational brain centered in the pre-frontal cerebral cortex. The two brains areconnected to one another, but operate inparallel to yield two different systems ofperception and memory. While neural path-ways between the emotional and the ratio-nal brain carry information in both direc-tions, the number of neural connectionsrunning from the limbic system to the cortexis far greater than the number connectingthe cortex to the limbic system (Carter1998; LeDoux 1996; Panksepp 1998). As aresult, not only do unconscious emotionalfeelings exist independently of rational ap-praisals of them, but given the asymmetryin neural connections between the limbicsystem and the neocortex, it is much morelikely that emotional impulses will over-whelm rational cognition than vice versa(Goleman 1995). To a great and unappreci-ated extent, therefore, our rational judg-ments about people and events reflect the

influence of emotional states that are trans-mitted unconsciously from our emotionalbrain to our rational brain.

Rational and Emotional

Perceptions

The emotional brain not only precedes therational brain in evolutionary time—it pre-cedes it in the order of perception. Researchin neuroscience shows that stimuli from theexternal world are perceived, evaluated, andacted upon by the emotional brain before therational brain has received the pertinent in-formation (LeDoux 1996). By the time therational brain receives incoming sensorystimuli about an event or object in the realworld, the emotional brain has alreadyswung into action and showered the neocor-tex with emotional messages that conditionits perception.

Figure 6 presents a simplified schematicdiagram showing how incoming stimuli areprocessed by the human brain. Sensory per-ceptions enter the brain and go to the thala-mus, where the signal is dispatched to boththe rational and emotional brains, which are,of course, connected to one another. But thetiming of the neural signal’s arrival in theemotional and rational brains is different, sothat the former is activated first. The func-tioning of the two brains can be illustratedwith a vignette.

Say you are walking in a crosswalk andsuddenly a car runs a red light and bearsdown upon you. The stimuli enter your eyesand ears. The perceptions travel along theoptic and auditory nerves to the thalamus,which sends the signal in two directions.One is the “high road” to the neocortex: firstto the appropriate sensory processing areaand then to the prefrontal cortex for rationalconsideration. There your rational brain willundoubtedly tell you that if you don’t movequickly you will be run over by the car, re-sulting in serious injury or death. Your fron-tal cortex issues instructions to motor areasin the parietal lobes to jump out of the way,and the message is relayed down the brainstem to the outlying nerves, which causeyour muscles to contract in such a way thatyou jump out of the way.

The foregoing account is consistent with amodel of rational choice. Your brain made a


quick cost-benefit calculation and decided itwas worth the expenditure of energy to jumpout of the way to avoid being run over bythe car. Given what we now know about howthe brain works, however, this account ofhuman action is completely incorrect(Goleman 1995; LeDoux 1996; Panksepp1998). By the time the rational brain has re-ceived the information about the oncomingthreat, the emotional brain has alreadyspurred your body into action and you willhave begun to jump out of the way. Yourheart will be pounding, and your breathingwill have accelerated. If you later try to ex-plain your behavior, you may say it all hap-pened so fast that you acted “without think-ing.”

But the action was a result of thinking; itwas unconscious thinking undertaken in thelimbic system. At the same time that thethalamus sent the visual and auditory infor-mation to the cortex for high-order process-ing, it also dispatched it along a “low road”to the amygdala, for what LeDoux (1996)calls “quick and dirty” processing. In con-trast to the “high road” through the neocor-tex, this lower route is shorter and faster.The amygdala immediately recognizes thethreat to survival posed by the oncoming carand sends a message to the hypothalamus tospur the body into immediate action.Adrenaline is released, your heart rate rises,your muscles contract, and in a split secondyou jump out of the way.

Laboratory studies indicate that informa-tion reaches the amygdala about a quarter ofa second before it reaches the prefrontal cor-tex. Thus, the emotional brain perceives thedanger and acts before the rational brain“knows” what is happening. In this case, hu-man behavior actually derived from theworkings of the older mammalian brainrather than the newer, more rational, butmuch slower neomammalian brain: If yourfrontal cortex were severed from the rest ofyour brain, thus disabling your rational fac-ulties, you would still jump out of the wayof the car.

In explaining human behavior it is thusimportant to distinguish between rationalityand rationalization. In the foregoing episode,a rational-theoretical account that explainsthe act of jumping out of the way as the re-sult of a rational cost-benefit decision is in-correct. This explanation is a rationalizationof behavior whose trajectory had alreadybeen determined in the emotional brain. Thelimbic system was the locus of action, notthe prefrontal cortex. An innate feature ofthe rational brain, however, is to rationalizeevents and behaviors. Thus, even though thebehavior, jumping away from the car,stemmed from prerational cognition, we feelcompelled to tell ourselves a logical storyabout what happened.

The power of rationalization has beendemonstrated in a famous experiment inwhich women were presented with a series

Amygdala(Emotional Brain)

(Rational Brain)

Response

Sensory Cortex

ThalamusStimulus

Somatic

Frontal Cortex

Figure 6. Schematic Representation of the Cognitive Processing of Emotion


of nylon stockings and asked to select thepair they liked best (Gazzaniga 1992). Whenasked why they had made their selection, allsubjects provided a lucid account referringto differences in quality, texture, color, size,workmanship, or style—even though thestockings were, in fact, identical. Accordingto one neuroanatomist, “we like to think of. . . action as the result of a rational decision,but it is really just the fulfillment of an im-pulse” (Carter 1998:41).

Rational and Emotional Memory

Not only does the emotional brain offer hu-man beings a second, parallel system of per-ception, it also provides a second memorysystem in which emotional states and feel-ings are recorded independently from infor-mation is consciously stored in the neocor-tex (Carter 1998; LeDoux 1996). That emo-tional memory exists is illustrated by thecase of a woman who, as a result of braindamage, had lost all ability to create newmemories. Every time her doctor saw her hehad to reintroduce himself. One day, how-ever, he held a pin in his hand before he in-troduced himself. When the woman shookhis hand, she recoiled in pain as the pinpunctured her skin. The doctor then left theroom and after a while came back. Oncemore he offered his hand in introduction. Al-though the woman did not recognize him,she refused to shake his hand. She could notsay why; she just wouldn’t do it:

[The doctor] was no longer just a man . . .but had become a stimulus with a specificemotional meaning. Although the patient didnot have a conscious memory of the situa-tion, subconsciously she learned that shak-ing [the doctor’s] hand could cause herharm, and her brain used the stored infor-mation, this memory, to prevent the unpleas-antness from occurring again. (LeDoux1996:181)

As mentioned before, the brain is highlylateralized, and in most people the left sideis devoted to analytic, logical, verbal think-ing, and the right side to emotional process-ing. That is, the left neocortex is used for ra-tional thought whereas the right amygdala isemployed for emotional processing (thereare right- and left-side amygdalas, like allbrain organs except the putamen). Each eye

receives and transmits information to bothsides of the brain at once: The right side ofboth eyes sends information to the right sideof the brain and the left side of both eyessends information to the left side. Brain re-searchers have developed special contactlenses that refract incoming light to one sideof the retina or the other, so that quite liter-ally, the left half of the brain does not knowthat the right side sees and vice versa. In oneexperiment, LeDoux, Wilson, and Gazzaniga(1977) showed disturbing images of peoplebeing thrown into flames to subjects wear-ing right-refracted lenses, which channeledthe information to the emotional brain butnot to the rational brain. Afterward the sub-jects had no declarative memory of whatthey had seen—they could only describe avague awareness of light and flashing—yetthey felt quite upset and disturbed. Althoughthey could not say why, they no longer likedthe experimenter or felt comfortable in hispresence.

Such unconscious learning reflects a basicbut powerful psychological process identi-fied long ago by the Russian physiologistIvan Pavlov (1927). In his experiments onclassical conditioning, an unconditionedstimulus (in the above example, a pin prick)is paired with a conditioned stimulus (thedoctor’s hand) to generate an unconditionedresponse (pulling away from the pin prick).As a result of the pairing, the conditionedstimulus (the doctor’s hand) becomes asso-ciated with the unconditioned stimulus (thepin prick) in the subject’s memory. Becausethe memory is stored in the amygdala, how-ever, it is not conscious, representing whatLeDoux (1996) calls an “implicit memory.”

Implicit memories exist independently ofand apart from explicit verbal memories andcontribute an underlying emotional valenceto the information that the neocortex stores.It is thus a basic feature of human cognitionthat all perceptions and memories have bothan implicit and an explicit content. Explicitcontent is laid down in conscious memory bythe hippocampus and stored in the cerebralcortex, whereas implicit content is filtered bythe thalamus and stored unconsciously in theamygdala. Indeed, it is only because objec-tive perceptions carry different emotionalvalences that we are even able to use ratio-nality to choose between them (Turner 2000).


Implicit memories are created through thepairing of stimuli with hard-wired emotionalor motivational states. Once an implicitmemory has been created and stored, it is re-markably durable and difficult to eliminate.

For our purposes, unconditioned stimulimay be divided into appetites and emotions.The former are internal conditions within thebody that send messages to the brain to in-stigate particular survival-related behaviors.Classical conditioning was first studied us-ing an appetite (hunger) in which Pavlov’sdogs were conditioned to salivate in re-sponse to a bell, which sounded just beforefood was presented. In the past few years,scientists have identified specific neuralstructures, pathways, and transmitters asso-ciated with basic appetites such as hunger,thirst, tiredness, lust, playfulness, and curi-osity (Carter 1998; LeDoux 1996; Panksepp1998).

There also appear to be specific neuralassemblies associated with the fundamentalhuman emotions such as fear, anger, dis-gust, nurturing, and liking (Panksepp 1998).Although some of the neurological mecha-nisms (such as fear) are better worked outthan others (such as disgust), all appear tobe mediated through specific neural struc-tures within the limbic system, thus creat-ing the possibility for classical conditioningby systematically pairing external stimuliwith emotional reactions to generate im-plicit memories that are stored in theamygdala. I believe that such unconsciousmemories created by intentional or inad-vertent conditioning lie behind much hu-man social behavior.

THE LIMITS OF RATIONALITY

My review of human evolution and cogni-tion yields six basic facts which, I believe,bring to question our overreliance on ratio-nality in explaining human behavior. (1)Emotionality preceded rationality in humanevolution. Our ancestors lived in structuredsocial communities grounded in emotionlong before they developed rational facul-ties. (2) The ability to evaluate potentialcosts and benefits of hypothetical actionsand to use these evaluations in planning forthe future—the essence of what most theo-retical models mean by rationality—

emerged very late in human evolution. Wehave only possessed the neurological equip-ment for such mental operations for less than3 percent of our time on earth. (3) Once weacquired the physiological capacity for ratio-nal thought, it took additional time to de-velop the mental devices necessary for ratio-nal cognition and analysis. Although ana-tomically modern human beings appeared150,000 years ago, symbolic thoughtevolved a full 100,000 years later than that.(4) It took another 45,000 years for spokenlanguages to be systematized in writing, cre-ating the possibility for the external storageof information and the emergence of an in-cipient rational culture. (5) Even after theseartifacts had been invented, it took another5,000 years for them to be inculcated withina majority of human beings, offering for thefirst time the possibility of a mass societybased on rationality. (6) And finally, despitethe recent flowering of rationality, evolutionhas bequeathed us a cognitive structure withtwo mentalities—one emotional and one ra-tional. While these two processors are inter-connected, emotional cognition precedes ra-tional cognition in evolutionary time and inreal time, and feedback between the two issuch that emotional traffic into the rationalbrain dominates that going in the reverse di-rection.

These six facts lead me to the inescapableconclusion that human decisions, behaviors,and social structures cannot be modeledsolely as a function of rationality. My read-ing of human evolution and cognition sug-gests that rationality, rather than being adominant and deep-rooted force in humanaffairs, is quite recently arrived and ratherfragile. To the extent that rationality mani-fests itself in social life, it is only because ofcultural practices and cognitive habits thathave been painstakingly acquired over mil-lennia and deliberately passed on to succeed-ing generations. Emotionality remains astrong and independent force in human af-fairs, influencing perceptions, coloringmemories, binding people together throughattraction, keeping them apart through ha-tred, and regulating their behavior throughguilt, shame, and pride. By failing to theo-rize emotion and by ignoring interactionsbetween rational and emotional cognition,sociologists derive an incomplete and mis-


leading view of human social behavior. As Isuggest in the following examples, a seriousconsideration of the nature and working ofthe emotional brain has much to offer soci-ology.

The Origin of Norms and Values

Sociology used to explain behavior as stem-ming from norms and values. While theseconcepts have not disappeared from the dis-cipline, the thrust of recent theorizing hasbeen to explicate their rational foundationsand see them as fundamentally logical pro-cesses (see Becker 1996; Coleman 1990).Work on subjective social meanings has in-creasingly been left to our friends in anthro-pology, who unfortunately have taken a diveoff a postmodernist cliff. From my point ofview, however, the study of norms and val-ues should really be about interactions be-tween social structure and the emotionalbrain, and particularly about how familiesand communities act to create implicitmemories that link behaviors, places, ob-jects, experiences, and thoughts to subjec-tive emotional states, thus shaping future ra-tional behavior.

The way that parents teach values to chil-dren, for example, implicitly recognizes thecognitive structure pictured in Figure 6 (seepage 18), where emotional cognition pre-cedes rational discrimination and where,owing to the asymmetry of neural connec-tions (indicated by the heavier line goingfrom the amygdala to the prefrontal cortex),the emotional brain is in a better position toinfluence the rational brain than vice versa.Consider, for example, thoughts about sex.Although thinking about sex naturally leadsto the release of endorphins in the humanbrain to create pleasurable feelings, parentswho wish their children to avoid early sexualcontact endeavor to pair sexual stimuli andsymbols with negative emotions such asshame, guilt, and even pain to create a con-ditioned response that will cause the child,in adolescence, to remain chaste. If the con-ditioning is successful, the emotional brainwill send out negative, inhibiting messagesto the cortex when confronted with sexualstimuli. Of course, such conditioning carriesthe risk that it maybe all too successful,leading to sexual dysfunction in adulthood.

Consumer Markets

Neoclassical economics assumes that tastesand preferences are given and that peopleenter markets to satisfy them through the ra-tional process of utility maximization (for arecent attempt to move beyond this simplifi-cation, see Becker and Murphy 2000). Al-though professors of economics may acceptthese assumptions and use them to derivecomplicated behavioral models, their col-leagues in business schools do not. On thecontrary, professors of marketing for yearshave sought to teach students specificallyhow to influence preferences, tastes, andmotivations through advertising and publicrelations efforts. It has been years since theoverlords of Madison Avenue have tried toappeal to our rational brains in marketingconsumer products.

For example, what is the rational connec-tion between an entity labeled “the Swedishbikini team” and a popular brand of beer?Objectively there is none, of course—theimage is not intended to appeal to the ratio-nal brain. By systematically and repeatedlypairing the beer with attractive blond womenin bikinis, the TV ad seeks to create a condi-tioned response among young men—theprime demographic category of beer con-sumers. If the conditioning is successful—and in the course of any sporting event thepairings will surely be relentless—the sightof the relevant six-pack (the conditionedstimulus) will trigger an implicit memory ofthe endorphins released by the sight of vo-luptuous Swedish women to generate a feel-ing of attraction toward the product that willlead to its purchase.

Influencing Political Behavior

One frequently hears the disparaging epithet“social engineering” applied to liberals whoadvocate using government power to redis-tribute resources in society. In truth the realsocial engineers are today’s political con-sultants. These individuals, mostly conserva-tive, apply the methods of social science tomanipulate the emotional brain and thusshape perceptions of political actors andideas. They pair their candidate or positionwith positive emotional stimuli while link-ing opposing figures and ideas with negative


stimuli (Jamieson 1996). Given the inherentsurvival value of emotional reactions such asfear and rage—which prepare an organismto flee or fight—negative emotions tend tobe more powerful as conditioning stimulithan positive emotions, which yields agreater prevalence of negative ads in politi-cal campaigns. Attack ads would probablyalso predominate in commercial advertisingwere it not for libel laws.

A persistent question is why do candidatescontinue to rely so heavily on negative ad-vertising when surveys repeatedly show thatvoters disapprove of and dislike the tactic?The simple reason is that the attack adswork. Although voters express a rational dis-approval of negative campaigning, theiremotional brains nonetheless pay attentionto negative material, and the pairing of thenegative emotions they arouse with candi-dates and political positions shifts votes inthe expected direction by creating implicitmemories lodged in the amydgala that latershape rational cognition.

Increasingly political consultants use themethods of social science—surveys and fo-cus groups—not to hone rational argumentsbut to identify emotional triggers that can bepaired with people and platforms to createimplicit memories within the emotionalbrain. The 1994 Republican Contract withAmerica, for example, was less a coherentpolitical program than a list of 8 vague“principles” and 10 contradictory legislativeproposals that surveys and focus groups hadrevealed would appeal to different segmentsof the electorate. Their votes were thus“stitched together” to eke out a majority inthe house of representatives. What modernpolitical consultants have done is simply toroutinize and refine the tactics of panderingthat astute politicians have naturally em-ployed for generations (see Berezin 1997;Emirbayer and Goldberg 2001).

Fear, Prejudice, and Stereotyping

Increasingly, we have become a fearful soci-ety, harboring a variety of apprehensions andsuspicions about people and events that arecompletely out of proportion with the actualrisks in society (Davis 1998; Glassner 1999).These fears reflect rampant fear condition-ing achieved inadvertently by the media and,

sadly, often intentionally by political actorsin our image-driven postmodern world. As aspecies, we are programmed to pay close at-tention to violent and threatening events. Inthe natural world, violence is rare—butwhen it occurs our brains instantly tune in.Fear-inducing stimuli proceed directly to theamygdala and unleash a variety of somaticand emotional reactions that focus our atten-tion and put us on high alert before our ra-tional brain has had a chance to act (Carter1998; LeDoux 1996; Panksepp 1998). Eventhough our rational brain may quickly dis-cern that there is no particular threat, thechemicals released into the blood stream(e.g. adrenaline) persist for some time andyield extended feelings of excitation andarousal (Goleman 1995; LeDoux 1996).

Television programmers and movie pro-ducers have long understood the inherent at-traction of violent images, and over the yearsthey have steadily ratcheted up the incidenceand severity of violence in a variety of me-dia, from movies to the internet. Possibly themost important escalation of violence hasbeen on television news. Whereas seriouscrime dropped by 3 percent through the1980s and early 1990s, and while the mur-der rate fell by 9 percent and overall crimi-nal victimization dropped by 21 percent,news coverage of crime by the three majornetworks doubled and the reporting of mur-ders tripled (Freeman 1994; Zucchino 1994).In a typical news night in 1995, 29 percentof news time was devoted to violence andwell over half to crime, war, or disaster(Klite, Bardwell, and Setzman 1995). AsOrfield (1997) put it, “Stations are pushedtoward crime coverage because it representsattention-grabbing material while requiringlittle or no labor costs spent on backgroundresearch and because crime’s sensationalismgarners high Nielsen ratings in a competitivemarket” (p. 23).

Thus, despite constant or declining crimerates in the United States, Americans are ex-posed, albeit vicariously, to more crime andviolence than ever before, and consequentlyin a safer world they feel more vulnerableand threatened. What is important sociologi-cally, however, is the potential for condition-ing inherent in the repeated association ofthe emotional responses of fear and ragewith people, events, and actions that regu-


larly appear on the screen. As Glassner(1999) documents in his study of the “cul-ture of fear,” Americans have come to har-bor a host of irrational fears, not just ofcrime, but of dangerous drugs, monstermoms, killer kids, mutant microbes, planecrashes, and road rage.

Probably the most important fear condi-tioning that is accomplished by TV program-mers, however, is the implicit associationbetween violence and minorities, especiallyAfrican Americans. The repeated pairing ofminorities with fearful circumstances ontelevision cannot help but create highlynegative and largely unconscious memoriesassociated with groups such as blacks andHispanics, and the existence of these im-plicit memories can only serve to strengthenracial and ethnic stereotyping and perpetu-ate racism (Glassner 1999). The existence ofsuch manufactured fears and racist feelingsalso provide politicians with powerful emo-tional levers they can use to mobilize thewhite electorate (Edsall and Edsall 1991).

The most notorious example, but certainlynot the only one, is the famous Willie Hortoncommercial during the 1988 presidentialcampaign, in which the natural human ab-horrence to violence was systematicallypaired with Governor Michael Dukakis via aclearly racialized image. The commercialwas powerful and effective not only becauseit tapped deep into the fear system hard-wired in the brain but also because it drewupon racialized images established throughpast fear conditioning. The frequent deliber-ate use of racist imaging for short-term po-litical gain is certainly one of the most dis-graceful practices to emerge in modern poli-tics, whether in the United States, in theBalkans, or in Rawanda.

The Effects of Urbanism

For my last example of how emotion influ-ences human affairs, I return to the fact thatwe are on the verge of becoming, for the firsttime, a fully urbanized society. Increasinglyhuman beings will not only live in cities butthose cities will be very large, and the larg-est among them will be in poor countries ofthe Third World. As a result, among both de-veloped and developing societies, povertywill increasingly be urbanized and geo-

graphically concentrated. Within nations, thebulk of the poor will be housed in large ur-ban agglomerations, and within these areasthe poor will increasingly concentrate inpoor neighborhoods, thus driving the spatialconcentration of poverty to new heights(Massey 1996).

Sociologists have long been fascinatedwith the influence of urbanism on social life.A classic statement was offered by Wirth(1938), who argued that the size, density,and heterogeneity of industrial cities wouldundermine social cohesion to promote indi-vidual alienation and social malaise. Al-though subsequent research has failed toconfirm his hypothesis, (Fischer 1975, 1982,1995), that didn’t stop a second round oftheorizing about the pathological effects ofpopulation density based on animal models(Calhoun 1962; Christian 1963). Once again,however, the expected relationship failed tomaterialize (Carnahan, Gove, and Galle1974; Gove and Huges 1983; Winsborough1970).

More recent work, however, has confirmeda clear relationship not between populationdensity and social maladies but between theconcentration of poverty and deleterious out-comes (Brooks-Gunn, Duncan, and Aber1997; Sampson, Morenoff, and Earls 1999).Here, understanding function and operationof the emotional brain is of potentially greatimportance in illuminating the link betweenconcentrated deprivation and behavior.

Among other things, areas of concentratedpoverty are characterized by high rates ofcrime, violence, and social disorder (Massey2001). Inhabitants of poor neighborhoodsare likely to experience high rates of expo-sure to danger, causing the amygdala fre-quently to send out signals that cause the re-lease of stress-induced hormones into theblood (Kotulak 1997; LeDoux 1996;Panksepp 1998). When threats of violenceare infrequent, such a response is highlyadaptive; but when violence becomes en-demic, serious physiological side effectsmay occur as a result of overloading thestress system, leading to the impairment oflearning (Diamond and Rose 1993, 1994),the degeneration of memory (McEwan1992), a greater propensity toward violence(Goleman 1995; James et al. 1987; Kotulak1997), and a greater risk of coronary heart


disease and other health problems (McEwan1999; Peyrot, McMurry, and Kruger 1999;Taylor, Repetti, and Seeman 1999).

Exposure to violence has the potential ofaffecting social conditions many times re-moved from the neighborhoods in which theviolence originally occurred. This was re-cently brought home to me with some force.With colleagues I am presently conducting astudy of students at elite colleges and uni-versities around the country. In the fall of1999 we interviewed cohorts of white,Asian, black, and Latino freshmen enteringthe nation’s most selective colleges and uni-versities (see Massey, Charles, Lundy, andFischer 2002). Among other things, we wereinterested in the sorts of neighborhoods inwhich the respondents had grown up. Asthey had already been selected by virtue oftheir admission to highly exclusive collegesand universities, we expected a certain ho-mogenizing of experience, and this was cer-

tainly the case for whites and Asians. Blacksand Latinos, however, evinced much higherrates of exposure to neighborhood violence,which was highly conditioned by the degreeof residential segregation they had experi-enced while growing up.

We designed an index of exposure to vio-lence that was weighted to capture not onlythe incidence of violence but its severity aswell, as measured by well-known the Sellin-Wolfgang scale (Sellin and Wolfgang 1964).Figure 7 shows this index for whites andAsians compared with blacks and Latinosclassified by the type of neighborhood inwhich they grew up: integrated, mixed, orsegregated. As can be seen, black and Latinostudents who grew up in integrated neigh-borhoods had roughly the same exposure tocrime and violence as whites and Asians. Incontrast, those growing up in segregatedneighborhoods experienced a degree of ex-posure to violence that was six times that of

0

100

200

300

400

500

600

700

Whites Asians Integrated Mixed Segregated

Group and Neigborhood Type

Vio

lenc

e In

dex

Blacks and Latinos

N = 998N = 959

N = 838

N = 552

N = 577

Figure 7. Average Exposure in Childhood to Neighborhood Violence by Neighborhood Type:Freshmen from Elite U.S. Universities

Source: Massey, Durand, and Malone (2002).

Note: Integrated neighborhoods are less than 30 percent minority; mixed neighborhoods are 30 to 60 per-cent minority; segregated neighborhoods are greater than 70 percent minority. The Violence Index is thenumber of violent acts to which a respondent was exposed while growing up, weighted by the severity of theviolence as measured by the Sellin-Wolfgang Scale (Sellin and Wolfgang 1964).


whites or Asians. Given what we know aboutthe effect of stress hormones on cognition, itis quite possible that such high levels of ex-posure to violence have long-term effects onmemory, learning, and temperament, a hy-pothesis that we will certainly consider inour future work.

FINAL THOUGHTS

I have presented just a few of the ways inwhich an appreciation for the role of emo-tionality in human affairs can enhance thesociological understanding of the humancondition. Given the parallel operation of theemotional and the rational brain within ev-ery human being, it is inevitable that alljudgments, perceptions, and decisions willhave both emotional and rational compo-nents. Moreover, because of our evolution-ary history and cognitive structure, it is gen-erally the case that unconscious emotionalthoughts will precede and strongly influenceour rational decisions. Thus our much-val-ued rationality is really more tenuous thanwe humans would like to believe, and itprobably plays a smaller role in human af-fairs than prevailing theories of rationalchoice would have it.

Our colleagues engaged in the practicalapplication of social science—marketing,advertising, and political campaigning—have known this for some time. They havenot simply recognized the duality betweenthe emotional and the rational brain, buthave sought to cultivate and exploit it. Thesocial engineering they practice has ad-vanced considerably and become extremelyeffective in shaping behavior, even as aca-demic theorists have relegated emotionalityto the back burner and devoted more atten-tion to a fully rational account of human so-ciety. Assuming rationality makes the worldneater and cleaner, of course, for it allowsthe use of higher mathematics in modelingsocial structures and behavior. But the evi-dence is incontrovertible that human behav-ior has both rational and emotional compo-nents and that the latter cannot be reducedto the former. On the contrary, if anything,emotionality supersedes rationality in bothtiming and influence.

If my arguments are correct, therefore,sociologists must work to understand more

fully our evolutionary history; we shouldreacquaint ourselves with the anthropologi-cal literature on hunter-gatherer societies;we must look to studies of primatologistsfor a window on the prerational origins ofsocial behavior; we must ground ourselvesmore firmly in the emerging literature incognitive neuroscience; and finally, wemust end our hostility to the biological sci-ences and work to incorporate the increas-ingly well-understood biological founda-tions of human behavior into our theoreticalmodels.

I am not saying that emotion is totally ab-sent from social theory and research, ofcourse. Indeed, it has been addressed by so-cial theorists from classical times to thepresent (see Barbalet 1998; Collins 1975,1993; Elster 1999; Turner 2000) and has at-tracted considerable attention from empiri-cal sociologists (Hochschild 1983; Katz2000). To date, however, most sociologistshave approached emotion in more philo-sophical than scientific terms, building edi-fices on assumptions and speculations aboutthe nature of emotion rather than on provenfacts. With the great advances already madein cognitive neuroscience and with those onthe horizon, we no longer must rely on as-sumptions. Rather, echoing Turner (2000), Ibelieve that we can and should ground ourtheories and models in established knowl-edge about how people think and interactusing both their emotional and rationalbrains.

Douglas S. Massey is the Dorothy Swaine Tho-mas Professor at the University of Pennsylvaniaand Chair of the Department of Sociology there.His research interests are in race, ethnicity, andimmigration. His latest book is Beyond Smokeand Mirrors: Mexican Immigration in an Era ofFree Trade (with Jorge Durand and Nolan J.Malone, Russell Sage, 2002).

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