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What Makes Us Curious

About The Book

Astrophysicist and author Mario Livio investigates perhaps the most human of all our characteristics—curiosity—in this “lively, expert, and definitely not dumbed-down account” (Kirkus Reviews) as he explores our innate desire to know why.

Experiments demonstrate that people are more distracted when they overhear a phone conversation—where they can know only one side of the dialogue—than when they overhear two people talking and know both sides. Why does half a conversation make us more curious than a whole conversation?

“Have you ever wondered why we wonder why? Mario Livio has, and he takes you on a fascinating quest to understand the origin and mechanisms of our curiosity. I thoroughly recommend it.” (Adam Riess, Nobel Prize Winner in Physics, 2011). Curiosity is not only at the heart of mystery and suspense novels, it is also essential to other creative endeavors, from painting to sculpture to music. It is the principal driver of basic scientific research. Even so, there is still no definitive scientific consensus about why we humans are so curious, or about the mechanisms in our brain that are responsible for curiosity.

In the ever-fascinating Why? Livio interviewed scientists in several fields to explore the nature of curiosity. He examined the lives of two of history’s most curious geniuses, Leonardo da Vinci and Richard Feynman. He also talked to people with boundless curiosity: a superstar rock guitarist who is also an astrophysicist; an astronaut with degrees in computer science, biology, literature, and medicine. What drives these people to be curious about so many subjects?

An astrophysicist who has written about mathematics, biology, and now psychology and neuroscience, Livio has firsthand knowledge of his subject which he explores in a lucid, entertaining way that will captivate anyone who is curious about curiosity.


Why? ONE Curious
INDEPENDENT OF THEIR LENGTH, SOME stories can leave lasting impressions. “The Story of an Hour,” a very short tale by the nineteenth-century author Kate Chopin, opens with a rather startling sentence: “Knowing that Mrs. Mallard was afflicted with a heart trouble, great care was taken to break to her as gently as possible the news of her husband’s death.” Loss of life and human frailty all packed into one punchy line. We then learn that it was the husband’s close friend, Richards, who brought the bad news, after having confirmed (by way of a telegram) that Brently Mallard’s name was indeed leading the list of those killed in a railroad disaster.

In Chopin’s plot, Mrs. Mallard’s immediate reaction is a natural one. Upon hearing the sad message from her sister Josephine, she starts weeping straightaway, then retires to her room, asking to be left alone. It is there, however, that something totally unexpected happens. After sitting motionless, sobbing for a while, her gaze apparently fixed on a distant patch of blue sky, Mrs. Mallard starts whispering a surprising word to herself: “Free, free, free!” This is followed by an even more exuberant “Free! Body and soul free!”

When she finally opens the door, yielding to Josephine’s worried requests, Mrs. Mallard emerges with “a feverish triumph in her eyes.” She starts to calmly descend the steps, clutching to her sister’s waist, while her husband’s friend Richards awaits them at the bottom of the staircase. That’s precisely when someone is heard opening the front door with a latchkey.

Chopin’s story contains only eight more lines beyond this point. Could we perhaps stop reading here? Needless to say, even if we wanted to, we probably wouldn’t, certainly not without at least knowing who was at the door. As the English essayist Charles Lamb wrote, “Not many sounds in life, and I include all urban and all rural sounds, exceed in interest a knock at the door.” That is the power of a story that pulls your attention with such force that you don’t even dream of overriding that pull.

The person entering the house is indeed, as you might have guessed, Brently Mallard, who, it turns out, had been so far from the scene of the train accident that he didn’t even know it had happened. The vivid description of the emotional roller-coaster ride that the temperamental Mrs. Mallard has had to endure in the span of just one hour turns reading Chopin’s drama into a riveting experience.

The last sentence in “The Story of an Hour” is even more unsettling than the first one: “When the doctors came they said she had died of heart disease—of joy that kills.” The inner life of Mrs. Mallard remains largely a mystery to us.

Chopin’s greatest gift, in my opinion, is her singular ability to generate curiosity with almost every single line of prose, even in passages describing situations in which apparently nothing happens. This is the type of curiosity that results from chills running up and down your spine, somewhat similar to the sensation you feel when listening to exceptional pieces of music. Those are subtle, intellectual cliffhangers that constitute a necessary device in any compelling storytelling, lesson at school, stimulating artistic oeuvre, video game, advertising campaign, or even simple conversation that delights rather than bores. Chopin’s story inspires what has been dubbed empathic curiosity—the standpoint we adopt when we try to understand the desires, emotional experiences, and thoughts of the protagonist and when her or his actions incessantly bother us with the nagging question Why?

Another element that Chopin aptly uses is that of surprise. This is a sure stratagem to kindle curiosity through heightened arousal and attention. New York University neuroscientist Joseph LeDoux and his colleagues managed to trace the pathways within our brain that are responsible for the reaction to surprise or fear. When we encounter the unexpected, the brain assumes that some action may have to be taken. This results in a rapid activation of the sympathetic nervous system, with its familiar, associated manifestations: increased heart rate, perspiration, and deep breathing. At the same time, attention is diverted from other, irrelevant stimuli and is focused on the key pressing element under consideration. LeDoux was able to show that in surprise, and in particular in fear response, fast and slow pathways are concurrently activated. The fast track proceeds directly from the thalamus, which is responsible for relaying sensory signals, to the amygdala, an almond-shaped cluster of nuclei that assigns affective significance and directs the emotional response. The slow track involves a lengthy detour between the thalamus and the amygdala that passes through the cerebral cortex, the outer layer of neural tissue that plays a key role in memory and thought. This indirect route allows for a more careful, conscious evaluation of the stimulus and for a thoughtful response.

Several “types” of curiosity—that itch to find out more—exist. British Canadian psychologist Daniel Berlyne charted curiosity along two main dimensions or axes: one extending between perceptual and epistemic curiosity and the other traversing from specific to diversive curiosity. Perceptual curiosity is engendered by extreme outliers, by novel, ambiguous, or puzzling stimuli, and it motivates visual inspection—think, for example, of the reaction of Asian children in a remote village seeing a Caucasian for the first time. Perceptual curiosity generally diminishes with continued exposure. Opposite perceptional curiosity in Berlyne’s scheme is epistemic curiosity, which is the veritable desire for knowledge (the “appetite for knowledge” in the words of philosopher Immanuel Kant). That curiosity has been the main driver of all basic scientific research and of philosophical inquiry, and it probably was the force that propelled all the early spiritual quests. The seventeenth-century philosopher Thomas Hobbes dubbed it “lust of the mind,” adding that “by a perseverence of delight in the continual and indefatigable generation of knowledge” it exceeds “the short vehemence of any carnal pleasure” in that indulging in it only leaves you wanting more. Hobbes saw in this “desire to know why” (emphasis added) the characteristic distinguishing humankind from all other living creatures. Indeed, as we shall see in chapter 7, it has been the unique ability to ask “Why?” that has brought our species to where we are today. Epistemic curiosity is the curiosity Einstein alluded to when he told one of his biographers, “I have no special talents. I am only passionately curious.”

To Berlyne, specific curiosity reflects the desire for a particular piece of information, as in attempts to solve a crossword puzzle or to remember the name of the movie you saw last week. Specific curiosity can drive investigators into examining distinct problems in order to understand them better and identify potential solutions. Finally, diversive curiosity refers both to the restless desire to explore and to the seeking of novel stimulation to avoid boredom. Today, this type of curiosity might manifest itself in the constant checking for new text messages or emails or in impatience while waiting for a new smartphone model. Sometimes, diversive curiosity can lead to specific curiosity, in that the novelty-seeking behavior may fuel a specific interest.

While Berlyne’s distinctions among different types of curiosity have proven to be extremely fruitful in many psychological studies, they should be regarded only as suggestive until a more comprehensive understanding of the mechanisms underlying curiosity emerges. At the same time, a few other types of curiosity have been suggested, such as the empathic curiosity mentioned earlier, which do not neatly fall into Berlyne’s categories. There is, for instance, the morbid curiosity that results in rubbernecking; it invariably impels drivers to slow down and examine accidents on the highway and prompts people to gather en masse around scenes of violent crimes and building fires. This is the type of curiosity that reputedly generated a huge number of Google hits for the gruesome video showing the beheading of British construction worker Ken Bigley in Iraq in 2004.

In addition to the potentially different kinds, there are also varying levels of intensity that one can associate with assorted genres of curiosity. Sometimes just a snippet of information would suffice to satisfy the curiosity, as in some of the cases of specific curiosity: Who was it who said, “Injustice anywhere is a threat to justice everywhere”? In other instances, curiosity can propel someone into a passionate lifelong journey, as is occasionally the case when epistemic curiosity shepherds scientific inquiry: How did life on Earth emerge and evolve? There are also clear individual differences in curiosity, in terms of the frequency of its occurrence, the intensity level, the amount of time people are prepared to devote to exploration, and in general the openness to and preference for novel experiences. For one person, an old bottle washing ashore on Amrum Island on the German North Sea coast may be just that: a disintegrating symbol of pollution. For another, such a find could trigger an opportunity for a glimpse into an earlier, fascinating world. A message in a bottle found in April 2015 proved to be from sometime between 1904 and 1906—the oldest-known message in a bottle. This was part of an experiment to study ocean currents.

Similarly, Ed Shevlin, a twenty-two-year New York City sanitation worker who collects trash five mornings a week, felt such great enthusiasm for the Gaelic language of Ireland that he enrolled in an NYU master’s degree program in Irish American studies.

About two decades ago, a rare astronomical event beautifully illustrated how a few supposedly distinct types of curiosity, such as that evoked by novelty and the one representing the thirst for knowledge, can combine and feed each other to form one irresistible attraction. In March 1993, a previously unknown comet was spotted orbiting the planet Jupiter. The discoverers were veteran comet hunters, husband and wife astronomers Carolyn and Eugene Shoemaker and astronomer David Levy. Since that was the ninth periodic comet identified by this team, the object was named Shoemaker-Levy 9. A detailed analysis of the orbit suggested that the comet had probably been captured by Jupiter’s gravity a few decades earlier, and during a catastrophically close approach in 1992, it broke up into pieces due to strong tidal (stretching) forces. Figure 1 presents an image taken by the Hubble Space Telescope in May 1994, showing the resulting two dozen or so fragments as they continued their course along the comet’s path like a string of shining pearls.

Figure 1

Excitement in the astronomical world and beyond started to rise when computer simulations indicated that the fragments were likely to collide with Jupiter’s atmosphere and to plow into it in July 1994. Such collisions are relatively rare (although one such impact on the Earth some 66 million years ago proved to be extremely unfortunate for the dinosaurs) and none had previously been directly witnessed. Astronomers all across the globe were waiting in eager anticipation. Nobody knew, however, if the effects of the impact would actually be visible from Earth or whether the fragments would simply be serenely swallowed by Jupiter’s gaseous atmosphere like tiny pebbles by a large, undisturbed pond.

The first icy chunk was expected to hit on the evening of July 16, 1994, and almost every telescope on the ground and in space, including Hubble, was directed at Jupiter. The fact that dramatic astronomical phenomena can seldom be observed in real time (it takes light many years to get to Earth from numerous objects of interest, but only about half an hour from Jupiter) gave this event a “once in a lifetime” feel. Not surprisingly, therefore, a group of scientists, myself included, gathered around a computer screen as the data were about to be transmitted down from the telescope (Figure 2). The question on everybody’s mind was: Would we see anything?

Figure 2

If I had to give a title to Figure 2, I know exactly what it would be: Curiosity! To feel curiosity’s contagious appeal, all you need to do is examine the posture and facial expressions of the scientists involved. As soon as I saw this photo on the following day, it reminded me of an extraordinary work of art executed almost four hundred years earlier; Rembrandt’s The Anatomy Lesson of Dr. Nicolaes Tulp (Figure 3). The painting and the photograph are almost identical in how they capture the emotion of impassioned curiosity. What I find especially fascinating is the fact that Rembrandt’s focus is neither on the anatomy of the flayed corpse being dissected (though the muscles and tendons are quite accurately depicted), nor even on the identity of the dead man (a young coat thief named Aris Kindt, hanged in 1632), whose face is partially shaded. Rather, Rembrandt was primarily interested in accurately expressing the individual reactions of each of the medical professionals and apprentices attending the lesson. He put curiosity at center stage.

Figure 3

Curiosity’s powers extend above and beyond its perceived potential contributions to usefulness or benefits. It has shown itself to be an unstoppable drive. The efforts humans have invested, for instance, in exploring and attempting to decipher the world around them, have always far exceeded those needed for mere survival. It seems that we are an endlessly curious species, some of us even compulsively so. University of Southern California neuroscientist Irving Biederman says human beings are designed to be “infovores,” creatures that devour information. How else would you explain the risks people sometimes take to scratch that curiosity itch? The great Roman orator and philosopher Cicero interpreted Ulysses’s sailing past the island of the Sirens as an effort to resist epistemic curiosity’s lure: “It was not the sweetness of their voices, nor the novelty and diversity of their songs, but their professions of knowledge that used to attract the passing voyagers; it was the passion for learning that kept men rooted to the Sirens’ rocky shores.”

French philosopher Michel Foucault beautifully describes a few of curiosity’s inherent characteristics: “Curiosity evokes ‘care’; it evokes the care one takes of what exists and what might exist; a sharpened sense of reality, but one that is never immobilized before it; a readiness to find what surrounds us strange and odd; a certain determination to throw off familiar ways of thought and to look at the same things in a different way; a passion for seizing what is happening now and what is disappearing; a lack of respect for the traditional hierarchies of what is important and fundamental.”

As we shall see, modern research suggests that curiosity may be essential for the proper development of perceptual and cognitive skills in early childhood. There is also little doubt that curiosity remains a powerful force for intellectual and creative expression later in life. Does this mean that curiosity is a straightforward product of natural selection? If it is, why do even seemingly trivial matters sometimes make us vehemently curious? Why do we occasionally strain to decipher the hisses of a conversation at the table next to us in a restaurant? Why do we find it harder not to listen to someone talking on the phone (when we hear only half of the conversation) than to listen to two people having a face-to-face exchange? Is curiosity entirely innate, or do we learn to become curious? Conversely, do adults lose their childhood curiosity? Has curiosity evolved during the 3.2 million years that separate Lucy—the transitional, nearly human creature whose bones were found in Ethiopia—from the Homo sapiens, modern humans? Which psychological processes and which structures within our brains are involved in being curious? Is there a theoretical model of curiosity? Do some neurodevelopmental disorders such as ADHD represent curiosity “on steroids” or curiosity spinning its gears?

Before seriously delving into the scientific research on curiosity, I decided (out of my own personal curiosity) to take a brief detour to closely examine two individuals who, in my view, represent two of the most curious minds to have ever existed. I believe that few would disagree with this characterization of Leonardo da Vinci and the physicist Richard Feynman. Leonardo’s boundless interests spanned such broad swaths of art, science, and technology that he remains to this day the quintessential Renaissance man. Art historian Kenneth Clark appropriately called him “the most relentlessly curious man in history.” Feynman’s genius and achievements in numerous branches of physics are legendary, but he also pursued fascinations with biology, painting, safecracking, bongo playing, attractive women, and studying Mayan hieroglyphs. He became known to the general public as a member of the panel that investigated the space shuttle Challenger disaster and through his best-selling books, which are chock-full of personal anecdotes. When asked to identify what he thought was the key motivator for scientific discovery, Feynman replied, “It has to do with curiosity. It has to do with wondering what makes something do something.” He was echoing the sentiments of the sixteenth-century French philosopher Michel de Montaigne, who urged his readers to probe the mystery of everyday things. As we shall see in chapter 5, experiments with young children have demonstrated that their curiosity is often triggered by the desire to understand cause and effect in their immediate surroundings.

I don’t expect that even a careful inspection of the personalities of Leonardo and Feynman will necessarily reveal any deep insights into the nature of curiosity. Numerous previous attempts to uncover common features in many historical figures of genius, for instance, have exposed only a perplexing diversity with respect to the backgrounds and psychological characteristics of these individuals. Take the scientific giants Isaac Newton and Charles Darwin. Newton was distinguished by his unparalleled mathematical ability, while Darwin was, by his own admission, rather weak in mathematics. Even within classes of masterminds in a given scientific discipline, there appears to be an ambiguous array of qualities. Physicist Enrico Fermi solved very difficult problems at age seventeen, while Einstein was, relatively speaking, a late bloomer. This is not to say that all efforts to identify a few shared characteristics are doomed to fail. In the area of prodigious creativity, for example, University of Chicago psychologist Mihaly Csikszentmihalyi has been able to unearth a few tendencies that appear to be associated with most unusually creative persons (those are briefly described at the end of Chapter 2). I therefore thought it a worthwhile exercise at least to explore whether there was anything in the fascinating personalities of Leonardo and Feynman that could provide a clue about the source of their truly insatiable curiosity. The key point for me was the fact that irrespective of whether Leonardo and Feynman had anything in common other than their curiosity, they both stood so high above their respective surroundings in terms of their spirit of inquiry that any stab at viewing things from their perspective was bound to be stimulating. I start with Leonardo, who once elegantly expressed his own passion for comprehension by saying, “Nothing can be loved or hated unless it is first understood.”

By the way, in case you are curious to know whether we actually saw anything when the first fragment of Comet Shoemaker-Levy 9 hit Jupiter’s atmosphere—we did! At first there was a point of light above Jupiter’s edge. As the fragment penetrated the atmosphere, it produced an explosion that resulted in a mushroom cloud similar to that created by a nuclear weapon. All the fragments left visible “scars” (areas with sulfur-bearing compounds) on Jupiter’s surface (Figure 4). Those smudges lasted for months until they were smeared out by streams and turbulence within Jupiter’s atmosphere, and the debris diffused down to lower altitudes.

Figure 4

About The Author

Photograph by J. Coyle Jr.

Mario Livio is an internationally known astrophysicist, a bestselling author, and a popular speaker who has appeared on The Daily Show60 Minutes, and NOVA. He is the author of the bestsellers The Golden Ratio, Brilliant Blunders, and Galileo. He lives in Baltimore, Maryland.

Product Details

  • Publisher: Simon & Schuster (May 22, 2018)
  • Length: 272 pages
  • ISBN13: 9781476792101

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Raves and Reviews

“Have you ever wondered why we wonder why? Mario Livio has, and he takes you on a fascinating quest to understand the origin and mechanisms of our curiosity. I thoroughly recommend it.”

– Adam Riess, Nobel Prize Winner in Physics, 2011

"Lively. . . . Provocative."

– USA Today

“Filled with fascinating stories, tidbits, and psychological insights, Why? is a delightful romp through every aspect of human curiosity. It will surprise you, make you smarter, and put a spring in your step.”

– Steven Strogatz, Schurman Professor of Applied Mathematics, Cornell University, and author of The Joy of X

“In Why?, astrophysicist Mario Livio argues that humans are the only species to ask not just what, where or who, but also why. . . . [He} includes some fascinating tidbits along the way."

– Katherine Harmon Courage, The Washington Post

"A lively, expert, and definitely not dumbed-down account of why we're curious."

– Kirkus Reviews

"This cogent book presents the scientific research on curiosity in understandable ways without too much jargon. It answers many (although not all) of our potential questions about curiosity—including what many originally believed killed the cat."

– Joseph Peschel, Science

“It’s impossible to imagine creativity or invention without curiosity, and one could hardly ask for a richer or more engaging exploration of human curiosity than the one provided by Mario Livio in Why?. This book is an intellectual feast for any curious person."

– Jeffrey M. Schwartz MD, Research Psychiatrist UCLA, author of (with Sharon Begley) The Mind and the Brain and (with Rebecca Gladding) You are Not Your Brain

"An energetic look at the psychology and neuroscience of our inquisitiveness."

– Dan Jones, Nature

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