Baltimore scientist and author Mario Livio has so many books crowded onto the shelves of his home near Quarry Lake that the thick white boards sag beneath the weight.
And those are just the shelves holding the art books in Livio’s living room. The scenario is repeated in every room in the home that the 72-year-old astrophysicist shares with his wife. There are bowed shelves holding physics texts, warped shelves holding books about classical music, shelves crammed with literary classics — and an overburdened shelf holding the six books of popular science that Livio has written himself.
The perpetually inquisitive Livio is coming to the Ivy Bookshop Tuesday to celebrate the paperback launch of his most recent book — “Why? What Makes Us Curious,” a round up of studies mostly in neuroscience and psychology that explore the nature of the trait that arguably is the most human characteristic — the drive to ask not just “what?” but “how?” and “why?”
“I think this book is very timely,” Livio says. “Curiosity is the best remedy for fear. Every breakthrough introduces new questions and uncertainties. Very often the things we are afraid of are the things we don’t understand — such as refugees. If instead of labelling every refugee as a terrorist or criminal we actually were curious enough to look at them in depth, we would be much less frightened.”
The book also examines the lives of two extraordinarily curious historical figures, the artist and inventor Leonardo da Vinci and the physicist Richard Feynman, while including interviews with such famously curious cultural leaders as Brian May, an astrophysicist and the lead guitarist of the rock band Queen.
Not that Livio himself is any slouch in the curiosity department. He was born in Romania and raised in Israel, where he served as a paramedic in three wars while earning his doctorate in theoretical astrophysics in the late 1970s from Tel Aviv University. As a scientist, Livio researched the role played by supernova explosions in determining the rate of expansion in the universe. He worked with the Hubble Space Telescope from 1991 until 2015.
In addition, Livio has served as a “science adviser” for the Baltimore Symphony Orchestra and has participated in concerts exploring the links between science and music.
“Mario has this extraordinary ability to connect science to the arts and to then communicate that connection,” said Carol Bogash, the Baltimore Symphony Orchestra’s former vice president of education and community engagement who recruited Livio in 2012. “He has the most uncanny ability of anyone I’ve ever known to translate the most dense science for a general public. Mario seems to genuinely like talking to non-scientists. People love listening to him. The concerts that he was a part of were always filled to capacity.”
What we call “curiosity,” Livio suggests, might refer to different mental activities. When people are confronted with something so novel or bizarre that they move closer so they can inspect it visually, it activates a part of the brain associated with conflict. In that instance, curiosity might be our way of reducing unpleasant feelings.
Conversely, when someone is motivated by the love of knowledge for its own sake, the brain’s reward center lights up. It’s the same area of the brain activated by chocolate.
“We describe these both as ‘curiosity,’ but they are felt psychologically as very different states,” Livio said. “Maybe if we had known that from the beginning we might have called them by different names.”
Livio’s book delves into a tantalizing array of questions such as how human curiosity differs from that of our four-legged friends and whether the drive to learn new things declines as we grow older. He discusses some of the highlights below:
What’s the difference between curiosity and creativity?
People often confuse them, but they aren’t identical. Curiosity is necessary but insufficient for making a creative accomplishment. There are people who are curious about a lot of things but who never do anything with it. Creativity takes drive and persistence and talent.
What’s the relationship between our desire to learn something new and how much we already know about that particular subject?
We’re most curious about things that lie in the middle range between being totally predictable and therefore boring, and being totally unpredictable and therefore confusing and the cause of anxiety. If we know almost everything about a topic, we lose interest. If, on the other hand, we know almost nothing, we don’t know enough to be curious about it.
You call curiosity humans’ most defining characteristic. But aren’t animals curious, too?
Animals are curious. But they’re not curious about why or how something happens, especially when there are unseen causes. Only humans are interested in that.
In one interesting experiment [performed by researchers Daniel Povinelli and Sarah Dunphy-Lelii at the University of Louisiana at Lafayette] a bunch of 4-year-old kids and chimps were all given the same object. It looked completely symmetrical, but it had different weights inside so that it could not stand stably. When the object kept falling over, more than 60 percent of the 4 year-olds examined the object and tried to figure out what was going on. None of the chimpanzees did.
How did the human brain develop the ability to ask “why?”
This is an answer with several parts:
Bigger animals are able to collect more food than smaller animals, but they also need more energy. It turns out that the energy they can collect as a function of their mass grows more slowly than the energy they consume. That limits how big the animal can become.
On top of that, the amount of energy the brain utilizes in different animals is a function of how many neurons there are in the brain. Human brains use about 25 percent of the body’s total energy budget, even though the brain is only about 2 percent of our total body mass. The brains of other species are much cheaper to run.
In order to achieve a dramatic growth in brain size, humans had to become more efficient at getting energy out of the food they eat. They did that by different ways: by learning to cook their food, which permits a much more efficient digestion; by learning to use tools that helped them eat more protein-rich foods; by learning to walk upright, which takes less energy than walking on four limbs; and by shortening the gut, a big consumer of energy.
Humans ended up with brains that on average have 86 billion neurons. Gorillas, which have a much larger body size, have about 33 billion neurons. The human capacity to ask how and why was starting to evolve.
Is an individual person’s level of curiosity inherited?
All psychological characteristics have a very strong genetic component. Studies that have looked at identical twins and at siblings have shown that curiosity is genetic at the 50 percent level, which is a very high correlation. If your parents were curious, you will be too. But that means that the other 50 percent of how curious you will become is determined by other, environmental factors.
Does curiosity decline with age?
A lot of people have the feeling that our educational system is destroying the curiosity of our children.
But novelty-seeking naturally declines with age. Children are interested in cause and effect to a very high degree, so they ask “why?” a thousand times a day. Once they figure it out, they stop asking.
It’s only the ... aspects of curiosity associated with novelty-seeking that decline with age. The ... curiosity that we talk about as “a thirst of knowledge” remains fairly stable throughout our lives.
This interview has been edited and condensed.