Big Brain Theories

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Is Barry Bonds the greatest home-run hitter of all time?

Well, yes. And no.

In a Journal of Recreational Mathematics article shamelessly titled “Chemical Bonds” that I coauthored with Adam Posner ’08, Tom Sullivan ’08, and Katie Chambers ’08 last year, we concluded that Barry Bonds (the current record-holder with 762 home runs) is the only one of four sluggers—Willie Mays (Barry’s godfather, 660 career home runs), Babe Ruth (714), and Hank Aaron (755)—whose home-run proficiency (home-run percentage, slugging average, and on-base percentage plus slugging average) actually increased after turning 35 years of age. Our before-and-after (age 35) comparisons suggested that Bonds is either an ageless wonder or a player whose numbers should be viewed with some skepticism.

Still, is Bonds the greatest home-run hitter of all time? Among the four sluggers, Ruth had the highest career home-run percentage (8.5 home runs per 100 at-bats compared to Barry’s 7.7 per 100 at-bats, and Hank’s and Willie’s 6.1 per 100 at-bats). Moreover, if Babe Ruth had not spent the first five years of his career as a pitcher (albeit, an exceptional pitcher) for the Boston Red Sox, would Barry’s career home-run record have been within the range of Babe’s mathematical possibility? Well, probabilistically speaking, yes. If Ruth had been employed differently early in his career, I believe that the probability is greater than 50 percent that Babe Ruth would have hit 900 career home runs.

That is, if Ruth had not pitched on a regular basis early in his career, he would still be wearing the home-run crown . . . and Barry’s name would not be tagged with an asterisk.

—Paul M. Sommers is a professor of economics and
a regular contributor to the Journal of Recreational Mathematics

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Brainteaser: Are all even numbers greater than 4 equal to the sum of two primes*?

Perhaps, according to Goldbach’s Conjecture. On June 7, 1742, a Prussian mathematician named Christian Goldbach wrote to his illustrious friend, the Swiss mathematician Leonhard Euler, asking him whether every positive, even integer greater than or equal to 4 could be expressed as the sum of two primes. Euler replied that it certainly appeared so to him, but that he could not demonstrate why it must always be true. In fact, even today no one has been able to prove or to disprove Goldbach’s Conjecture.

Over the years, Goldbach’s Conjecture has been verified for larger spans of even integers. For example, by 1885, it was known that Goldbach’s Conjecture was true for all even integers up to 10,000. By 1938, it had been checked up to 100,000. With the advent of modern computers, these bounds have been dramatically increased. Currently, we know that every even integer less than one quintillion (1 with 18 zeros) is expressible as the sum of two primes (possibly in several ways). However, computations alone will never prove an assertion about all even integers since there are infinitely many of them (though it could conceivably find a counterexample if there is some even integer that is not the sum of two primes).

—Pete Schumer is the Baldwin Professor
of Mathematics and Natural Philosophy

*Recall that a prime number is an integer greater than 1 whose only factors are 1 and itself. The list of prime numbers begins with 2, 3, 5, 7, 11, 13, 17, 19, 23, etc.

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What is 'race'?

Race as a concept only came into full flower in the 18th
and 19th centuries. (At the time, it was used to designate people believed to share common ancestry or biological traits.) Apart from the well-known understanding we have today of race as skin color, it was also used to identify nations (the Irish race) or poor people (inferior breeds). In the 20th century, Nazi Germany took the “scientific” strand of “race thinking” to the extreme, and, in so doing, delegitimized race-as-biology among the vast majority of the scientific and social-scientific community.

Yet contrary to what we might have expected, race did not disappear as a concept. In part this was due to its continued use among ardent racists in places like South Africa and the American South, where it served as a wedge to divide and oppress millions of people. Beginning in the 1960s, it also became a vehicle for progressive politics in the United States and beyond through the civil rights movement, which used racial disadvantage as a mobilizing tool for promoting equality of opportunity.

Since World War II, social scientists have widely agreed that race is “socially constructed,” meaning that it is not grounded in any objective scientific reality, but it is nevertheless perceived by many people to be real and meaningful. As proof that it is socially constructed, it is possible to look around the world and note striking differences in what “race” means: in the United States it is strongly associated with skin color; in Japan it is linked to blood; and in Latin America it is closely tied to socioeconomic class, where, as the saying goes, “money whitens.”

Recent social developments and scientific discoveries are opening new frontiers in our understanding of race. With an increase of “mixed-race” marriages in the U.S., there are political movements afoot that challenge the assumption that children of these unions should be forced to choose just one race. Leading scholars are asking if Asian/white and Latino/white kids will assimilate to the white race, as Jews and Italians (then perceived as nonwhite) did in the 19th and early 20th centuries. Following the heavy lobbying of parents of “multi-racial” children in the 1990s, the 2000 U.S. census allowed respondents to “mark one or more” racial categories that they felt applied to them. This may open up space for individuals to change the way they think about race, and it may eventually have vast consequences for the country as a whole.

In addition, with the advent of DNA testing, people can begin to assess scientifically the origins of their ancestors. This development is especially delicate among Native American communities, where membership and rights can depend on ancestry. It raises the specter of using science to judge people’s race, but also offers the hope that many people will come to learn that they are the product of more geographical forebears than they had realized.

—Erik Bleich is an associate professor of political science

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When boomers retire, where will they go? And what will this mean for America's cities and towns?

As the baby boom generation enters retirement age, the United States may witness unprecedented urban to rural migration dramatically reshaping small towns and rural landscapes. Such migration dynamics will have profound economic implications, as the migrating boomers will transfer their wealth as they move.

Migration behavior is predictable throughout a person’s life. Migration rates are highest for those in their early 20s when individuals are establishing themselves independently, moving frequently from apartment to apartment or place to place. After a period of stability for people in their 30s and 40s, migration rates once again rise for those in their late 50s and early 60s, and these migration flows are quite distinct. Early in life, people tend to move toward urban and suburban locations. In contrast, migration at later stages tends to flow away from metro areas. As individuals near retirement, they often seek out non-metropolitan locations that offer a slower-paced lifestyle, access to recreational amenities, and possibly lower costs of living. This process is relatively consistent across the country, and is only going to be more substantial in the coming decades as the baby boomers age through their 50s and 60s. The more than 83-million boomers (currently between the ages of 44 and 62) will make approximately 250 million moves during the next 20 years, and many of these will be directed toward small towns and rural destinations.

Impacts on migrant origins are equally, if not more, profound. The baby boomers came of age in a rapidly suburbanizing America, and as they entered the housing markets in the 1970s and 1980s, suburban expansion accelerated. Today, the vast majority of baby boomers are living in suburbia, but as they age, they’re likely to leave their suburban locations and head to the country or back to the city. What happens to the vast residential landscapes of suburbia as the boomers leave? Can (will?) the smaller generation born in the late 1960s and 1970s fill the void the boomers will leave behind?

Of course, the income characteristics of an aging population also present distinct geographic implications. People in their 20s and 30s generate the bulk of their income through wages and salaries. (For those aged 30 to 35, more than 96 percent of personal income is derived this way.) However, as people age, the composition of personal income shifts dramatically toward “non-earnings” sources, such as stock dividends. For people between the ages of 70 and 75, more than 80 percent of their income is derived this way. In the aggregate, nearly 30 percent of total personal income today is derived from non-earnings sources, but this composition varies dramatically from place to place. For instance, there are some counties in the U.S. where more than 60 percent of personal income comes from non-earnings sources.

What does this mean? When coupled with age-specific-migration dynamics, characteristics of personal income sources can have a large impact on communities. As people move, they bring with them their non-earnings income, and this can mean sizable gains for destination communities—but also sizable losses for those communities left behind. Between 1995 and 2000, more than $50 billion in investment income moved from place to place, and this means that some communities received an economic windfall, while other areas saw this money leave town. So, with the boomers on the horizon, how will these nonmetropolitan communities change as they become more dependent on non-earnings income sources?

—Peter B. Nelson is an associate professor of geography

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If the United States is the most powerful country on the planet, why are we struggling in Afghanistan and Iraq?

While recent events might suggest that American power is on the wane, it is not the case: American power has been both misused and privatized.

Contractor activities in Iraq have received significant negative media attention, but most people are probably unaware that the publicized accounts are just the tip of an iceberg. In 2005, the U.S. government had a contract presence (U.S.-funded contractors working in a given territory) in every UN-recognized country in the world except Bhutan, Nauru, and San Marino. The U.S. government outsources things it used to do itself; at the same time, nongovernmental actors, with or without the explicit approval of Washington, have unprecedented power
to make their own foreign policy.

Since American power has been privatized, what were once exclusively American government functions have diffused to corporations, civic groups, and individual philanthropists. Many of these actors are American. But even where they are not, they comprise a global coalition that is animated by the universal values that America’s founders embraced as American. They believe in the power of free markets and in equality of opportunity. They strive to promote these values worldwide, just as the American government does, although in countless decentralized and more effective ways.

This vast web of actors from all sectors can be understood as an empire—a kind of empire that the world has never seen before. It is an empire because it is vast in its dominion, controlling riches and reaching to all corners of the earth. But unlike any previous empire in human history, it has no emperor, and it has no subjects. It is an empire of the willing.

That the U.S. presence in Iraq and Afghanistan has little to do with the empire of the willing’s values is a measure of our failure. Getting the United States back on course requires acknowledging that unenlightened government outsourcing—our present standard practice—has created an enormous accountability vacuum that has enabled three dangerous developments: (1) gross fiscal irresponsibility, (2) dangerous apathy among the public at large, and (3) the inadvertent militarization of American foreign policy.

While government outsourcing as presently practiced is scandalous, the solution is not to turn the clock back. We must instead insist that government collaborate with the private sector in ways that serve the public interest. The private sector, after all, is us. That American power has been privatized ultimately means that each and every one of us has potential power that individuals of another generation did not. Understanding the changing nature of American power
is the key to wielding that new power for the good.

—Allison Stanger is the James Jermain Professor of Political Economy and director of the Rohatyn Center for
International Affairs.

She elaborates on her answer in Empire of the Willing: The Privatization of American Power (New York: Basic Books, forthcoming).

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What effect does film have on reality?

Very few people ask any more if film is an art form worthy of serious study, which is good, since the question didn’t make sense anyway. No one asks if painting is an art form, but there are as many silly paintings as there are silly films. More and more now the question is not only about beauty but also truth, about how and in what ways moving images have become such a powerful institution that no matter how bogus, they influence formidably our understanding, our values, our emotions, our behavior, and consciousness itself.

Images are so potent and so ubiquitous that we can become enticed by them. The great Italian director Federico Fellini said that after he recreated Rome’s Via Veneto for his film La Dolce Vita, the real Via Veneto seemed fake to him. The image falsifies the real. The more we subject ourselves to compelling images, the more reality can seem vapid. Ironically, the more powerful moving images become, the less likely they are to be true. Maybe we no longer know what reality is, for what we encounter directly is too often inadequate compared to moving images. Thinking, feeling, and relationships suffer because they seem lacking. Discourse becomes loaded with examples from moving images. Reality seems dependent upon images of reality to make sense, opening up the possibility that the representation is the true. What is real becomes even less of a meaningful question. Since representations are always in some sense false, no matter how compelling, the impact of reality is diminished. We could become less connected, and concerned, with what we experience that is unmediated by moving images.

This picture is rather bleak. The solution, if there is a solution, is to become aware, to be able to step back and understand the impact of these various forms of moving images, from movies to television to video games to social networking sites. The critique of moving images becomes absolutely necessary.

—Ted Perry is the Fletcher Professor of the Arts

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Is there such a thing as a flame-retardent polar bear?

Probably not—although I haven’t actually attempted to set a polar bear aflame. This notion, however, may not be as far-fetched as it sounds. For decades, toxic chemicals have been detected in surprising concentrations in the Arctic: flame retardant chemicals in the fatty tissues of polar bears; DDT in the breast milk of indigenous women; stain-resistant coatings in the eggs of Arctic seabirds. But how exactly do these chemicals, known collectively as persistent organic pollutants (POPs), navigate northward to such remote areas, areas where the chemicals have never been produced or used?

The simplest explanation is that POP molecules are carried north on the whims of atmospheric and oceanic currents. More realistically, POP molecules arrive in the Arctic on wind and water only after thousands of complex layovers and detours. POPs’ halfhearted commitment to evaporation, known as their semivolatility, means that they evaporate in warm areas and condense in cold areas, accounting for their steady, if incremental, journey northward. A brief condensation layover might include resting on the waxy cuticle of a leaf before the heat of the morning sun revolatilizes the molecule and returns it to the atmosphere. An otherwise short stay adsorbed to phytoplankton at the base of the food web might lead to long-term biomagnified residence in the fatty tissues of top predators, an outcome dictated by the hydrophobic nature of POP’s molecular structures. And while POPs experience their share of layovers, hemispheric detours are also quite common. They are notorious for meandering thousands of miles downstream, adhered to the smallest sediment grains, and for piggybacking on plumes of transcontinental dust. And migratory birds carry POPs thousands of miles south along migration flyways, a detour that readily reverses direction the following spring and can hasten POPs’ Arctic arrival.

So how do persistent organic pollutants manage to survive their long and complex journeys to the Arctic? While many chemicals do not survive the combined environmental assaults of sunlight, microbes, and highly reactive atmospheric chemicals, POPs (as their name would suggest!) persist relatively unscathed—a result of their constituent halogen atoms. In fact, it is just this persistence that promoted their use in the first place. Think pesticides that require minimal reapplication and the 10-year-stain warranty on your carpet. POPs persistence only increases in the cold of higher latitudes by slowing down what are already slow degradation pathways. Of course POPs concentrations are much higher in ecosystems that neighbor production facilities and areas of intensive use than they are in the Arctic. The heavy POPs contamination
in Great Lakes ecosystems has had devastating effects on wildlife, and associated epidemiological studies reveal detectable reproductive and developmental consequences in humans. But it was the accumulation of POPs in the Arctic that caught scientists most off-guard.

Although many older POPs, most notably the “dirty dozen” covered by the Stockholm Convention, are now banned or severely restricted in many countries, newer and as yet unregulated ones remain in use, degrading local environmental health and serving as an ongoing source of global pollution.

What are the ethics of emitting substances whose harmful legacy long outlives their usefulness to society?
Can we avail ourselves of technological innovation without poisoning ourselves in the process? Is there a healthier balance to be found between precaution and presumed progress?

—Molly Costanza-Robinson is an assistant professor
of environmental chemistry

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Who gives?

More than two centuries ago, Adam Smith observed in his Wealth of Nations that “it is not from the benevolence of the butcher, the brewer, or the baker, that we can expect our dinner, but from their regard to their own interest.” Or, as Gordon Gekko, the villain of Wall Street, put it, “Greed, for lack of a better word, is good.”

In this context, the thousands of alumni who have contributed, or will contribute, to the Middlebury Initiative, would seem to be poor examples of homo economicus. Americans have a long-standing tradition of generosity, however. In 2006, the last year for which reliable data are available, Americans gave almost $300 billion. Furthermore, individuals, as opposed to corporations or foundations, were responsible for almost three-quarters of this amount and contributed more than $40 billion to education. So what motivates these “self-interested” individuals to donate their hard-earned dollars to charities and other nonprofits?

Economists posit that donors give for a variety of reasons. Some donors may be motivated by pure altruism: they give because they care about the well-being of the recipients or to show appreciation to an organization that has had an impact on their life. Others may derive “private benefits” from charitable giving: some donors, for example, may use their donation to “buy” access to free season tickets, lunch with powerful politicians, or membership in an elite club. Donors may give to signal wealth status or gain public recognition. Others may feel a social pressure to contribute. Still others may give to alleviate guilt for their own good luck or fortune.

Through careful analysis of surveys, giving records, federal tax returns, and, more recently, lab experiments, we have learned a great deal about the personal characteristics and motivations of givers. Not surprisingly, wealthier households tend to give more, especially those in the highest income tax brackets who live in states that offer deductions for charitable giving. Older individuals tend to donate more, even after controlling for wealth. Most studies show that women are more generous than men, although recent evidence suggests that men tend to concentrate greater income on fewer charities while women tend to spread their giving over more organizations. Those who attend religious services regularly give more than otherwise similar individuals, with the majority of their giving targeted toward religious organizations. Corporate and other fund-raising programs that offer donor matches have successfully increased both propensity to give and overall giving levels.

—Jeffrey Carpenter, Jessica Holmes, and Peter Hans Matthews are members of the economics department at Middlebury College and founding partners in Philanthropy Research Group

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Where does mass come from?

Einstein’s famous equation E = mc² tells us that the mass of an object is a measure of its energy content. For example, if m is the mass of this magazine in kilograms, then as it sits on your coffee table, it contains energy (E) equal to m times the square of the speed of light c—a rather large result, since the speed of light is approximately 300 million meters per second. But where does this mass—and therefore energy—come from?

Our modern understanding of all the particles and interactions in nature is based on a “unifying symmetry assumption” that seems to require fundamental particles to have zero mass. However, when you picked up this magazine, you probably noticed that the particles it is made of do have mass, in violation of this requirement. There is a clever resolution to this paradox, postulated by the Standard Model of particle physics: Fundamental particles are intrinsically massless, but effectively acquire a mass by interacting with an invisible soup, called the Higgs field, that fills all of space. What we observe as a heavy particle is really just a massless particle getting “bogged down” in this sticky soup.

Crazy as it sounds, this model is incredibly successful. It correctly describes every experiment ever carried out at a particle accelerator. It explains why some particles remain massless and precisely predicts a relationship between the masses of other particles, though the masses of most fundamental particles remain experimental inputs to the theory, not predictions. But, like Godot, the central player in this drama has not yet appeared: We have never observed the Higgs field directly—only its indirect effects through the masses it generates. There could be many Higgs fields, it could be a composite of new fundamental particles, or it could be replaced by an entirely different mechanism we haven’t imagined yet.

The Large Hadron Collider in Geneva, Switzerland, due to start operation this year, may resolve this unsatisfactory state of affairs. It will attempt to create ripples in the Higgs soup—analogous to sound waves in air—to observe the Higgs directly. Doing so will allow us to probe the structure of the Higgs field, potentially yielding new relationships between particle masses and unraveling the mystery of mass.

—Noah Graham is an assistant professor of physics

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How do we know that we know what we know?

We claim to know a great many things: nearly all of us claim to know things like “2 + 2 = 4” and “rocks exist”; scientists claim to know about the unobservable physical structure of the world; some of us would even claim to know certain artistic, moral, and religious truths. But how can we be sure that we know these things and are not merely opining about them?

There are many views on this matter. Some philosophers hold that we know things when they are justified on the basis of certain self-evident foundations. Some hold that these foundations are the abstract truths of logic and mathematics; others hold that they are the immediate experiences of our senses.

Still others, like myself, deny that there are any firm foundations. In principle, every belief is up for grabs,
and it is only its overall fit within a preexisting totality
of our beliefs that determines its warrant. As a result, beliefs that appear to be foundations depend on the social and historical context in which they arise. For example, tables and chairs may be perfectly stable foundations when making knowledge claims about the arrangement of furniture in a room, but are not such firm foundations when talking about atomic structure.

Throughout history, we have seen the seemingly firm foundations of Euclidean geometry and the authority of the “naked eye” give way to Riemannian geometries and electron microscopes. In short, what appears infallible and incorrigible today may very well be fallible and corrigible tomorrow.

—Kareem Khalifa is an
assistant professor of philosophy

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Can geography enhance our understanding of the Holocaust?

We certainly think so. To date, most studies of this horrific event have focused on the experience of individuals or communities, such as the Jewish community in the Warsaw ghetto or the grim operation of Nazi concentration camps. Very few have considered how the Holocaust unfolded spatially—how it happened as a geographical event. That’s about to change.

An international group of historians and geographers has begun a long-term research project that reconceives the
Holocaust as a profoundly geographical story. They are focusing on how the Holocaust set millions of people in motion across Europe through mass displacement and forced migration, the destruction or fundamental changes that affected thousands of communities, and the systems of transportation and place-making that enabled the Nazi machine to concentrate population, exploit slave labor, and kill millions of people.

The group has developed a long-term research agenda and is now beginning a number of collaborative research projects, with strong support from the U.S. Holocaust Memorial Museum in Washington, D.C. The common elements between all the projects are the use of visual evidence—such as historical maps and photographs—and visual and spatial methods of analysis using GIS (geographic information systems) and geographic visualization. By combining these relatively little-used sources and methods with more familiar historical material, such as victim testimonies and the extremely detailed records kept by the Nazis, the group aims to discover how the Holocaust developed, which regions and peoples were targeted when, and how the camps system evolved in relation to the war. Ultimately, we hope to understand how the complex Nazi system worked as a whole and how its implementation differed from place to place.

—Anne Knowles is an associate professor of geography
and a founding member of the Holocaust study group

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Are today's television writers the 21st-century versions of Charles Dickens?

One of the functions of a liberal arts education is to expose students to a rich history of cultural works, centuries of aesthetically groundbreaking and profound examples of literature, drama, visual art, and music. Does television belong in that list of artistic forms? When compared to Milton and Mozart, Michelangelo and Molière, even the best of television might seem to come up far short. But we need to remember that the distance of time often turns popular culture into art—18th-century novels were seen as a threat to traditional notions of culture and morality, and 19th-century masters like Austen and Dickens were not viewed exclusively as elite literature in their day. Shakespeare was seen as popular culture up through the 19th century, with performances for uneducated tavern-goers as a common part of American frontier culture. We have seen Hollywood films of the 1930s and 1940s shift from being regarded as cultural corruptions to the classical era of a new art form.

We may not be in an adequate position to imagine how today’s television might be viewed by future generations of critics and viewers. But I do dare to dream that television will undergo the same type of historical cultural revisionism as the novel and cinema previously experienced. Looking back on the late-20th and early-21st centuries, American television will be viewed as a fertile terrain of aesthetic achievement, with programs like The Sopranos and Arrested Development, The Simpsons, and Buffy the Vampire Slayer hailed as masterpieces of storytelling and social commentary. We can start laying that critical groundwork by studying the aesthetics of television explicitly, exploring what the medium can do that sets it apart from other media, and examining works that successfully reach lofty aesthetic heights. I am currently focusing my scholarly energies on the aesthetics of long-form television narratives, exploring how serial storytelling accomplishes artistic ambitions and offers a unique cultural form through its specific brand of narrative complexity.

For a specific example, the recently completed HBO series The Wire is arguably the great masterpiece of television drama—the program offers a compelling glimpse into America’s forgotten underclass, using fiction to make political and social arguments, much like Zola, Dickens, Stowe, and Sinclair accomplished in previous eras. Exploring life in the drug game, on the police beat, in city hall, in public schools, and on the docks of Baltimore, the show builds an emotionally compelling and intellectually complex world that has scaled aesthetic heights across its 60 hours over the past five seasons. Next spring, I will teach a course entitled Urban America and Serial Television: Watching The Wire, where Middlebury students will watch the entire series and study its aesthetics and social commentary, considering how the show might stand as the 21st-century equivalent of War and Peace, Bleak House, or the Oedipus Cycle. Together, we will work to find the artistry that is possible, and arguably best realized, on the small screen.

—Jason Mittell is an associate professor of American studies
and film & media culture

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What can an award-winning novel tell us about society?

Announcing that Kiran Desai’s The Inheritance of Loss had won the 2007 Booker Prize, Hermione Lee described it as “a magnificent novel of humane breadth and wisdom, comic tenderness and powerful political acuteness.” Desai’s subject is the predicament of people whose lives are blighted by larger forces: colonialism, nationalism, globalization, and above all, capitalist exploitation and poverty. These overbearing forces have painfully concrete effects that Desai conveys with nuance and wit. The novel is magnificent precisely because it tackles large questions of politics and identity with tremendous dexterity and empathy. The most unusual and impressive aspect of Desai’s writing is her ability to sustain a tone that is gently and affectionately ironic—at times comedic—while writing about unremittingly bleak circumstances.

We see this in Biju, a young man who has traveled from northeast India to New York to find work. In an early chapter, Biju loses his job:

Out of his depth, he was almost relieved when the manager of their branch received a memo instructing him to do a green card check on his employees.

“Nothing I can do,” the manager said, pink faced from having to dole out humiliation to these men. A kind man. His name was Frank—funny for a man who managed frankfurters all day. “Just disappear quietly is my advice… .”

So they disappeared.

Desai mitigates the harshness of the loss by suggesting that Biju is “almost relieved.” She introduces a tangential note of somewhat clumsy humor by remarking upon the absurd aptness of the manager’s name. The obviousness of the link the narrator makes between the man’s name and his occupation is offset by the somberness of his advice—“Just disappear quietly”—and the fact that they take it. The passage is layered and dynamic, moving fluidly between the grim and the droll, and ending with the ominous “disappeared.” Desai refuses to suggest that the people whom Biju encounters are overtly racist. She conveys, rather, the systemic nature of the inequalities of class and race in the postcolonial world. Using gentle irony and comedy, she succeeds in portraying the harshness of migrants’ lives without being condescending or voyeuristic.

—Yumna Siddiqi is an associate professor of English and American literatures

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Will we ever build truly intelligent machines?

The field of “artificial intelligence”—AI for short—was born in the summer of 1956 at Dartmouth College when a group of computer scientists pondered this very question. The group optimistically anticipated significant progress towards machine intelligence within months. Yet after a 30-year period of hope, hype, and ample funding, the true difficulty of the problem sank in, and funding for AI research all but disappeared. The lofty goal of a computer with human intelligence remains elusive today.

Of course, AI did have success stories along the way; for instance in 1997, when IBM’s Deep Blue chess computer beat reigning world champion Garry Kasparov. But this and similar feats were quickly discounted as being done with “brute force” rather than true intelligence. One of my favorite definitions of AI—“the study of how to make computers do things which, at the moment, people do better”—captures such disillusions: Once the feat is accomplished, it doesn’t seem so magical anymore. And surely the brain doesn’t work this way . . . does it?

The “engineering approach” of finding the most effective solution for a given problem (rather than of imitating nature) has a proud history —after all, cars don’t walk and airplanes don’t flap their wings. The situation is no different in AI and related fields, including my own research area: computer vision, the interpretation of images via computer programs.

I (and others) employ sophisticated algorithmic and mathematical techniques for problems such as stereo matching (build a 3D model from two images) or object recognition (find all the chairs in this image). It’s clear that the human brain does not (and cannot) use such methods. However, existing theories of brain function have been too vague to yield useful computer models, so the engineering approach appears to be the only avenue. And yet, while thousands of researchers have attacked these problems for half a century, toddlers still handily beat the best computer programs when it comes to recognizing people and identifying objects.

In his intriguing book, On Intelligence, Silicon Valley-
entrepreneur-turned-brain-researcher Jeff Hawkins argues that AI research has been misguided by defining intelligence in human terms. The famous Turing test, for instance, proclaims a machine intelligent if, in casual conversation via a computer terminal, it is indistinguishable from a human. According to Hawkins, such a human-centric perspective is doubly problematic: First, it requires modeling the entire baggage of human evolutionary history, including bodily senses, social interactions, and emotions. Second, it may overlook novel unhuman types of intelligence, which may potentially be the most beneficial.

Hawkins argues that the key characteristic of intelligence is the ability to detect, learn, and predict patterns among complex signals, as exhibited by the human brain. Translated to machines, this might for instance yield a global network of computers with atmospheric sensors that could learn weather patterns and give accurate weather forecasts —all without any preprogrammed climate models or other “input” of human intelligence.

Interestingly, Hawkins proposes to reach such machine intelligence by imitating nature after all: his goal is to decipher the “cortical algorithm” employed in the brain, a hierarchical computation that detects, learns, abstracts, and eventually predicts any type of pattern.

How soon will we get there? According to Hawkins, perhaps within our lifetimes. In the meantime, we’ll have to make do with the engineering approach and build artificial intelligence on top of human intelligence.

—Daniel Scharstein is an associate professor of computer science