Curiosity

It's not just a rover.

Isaac Asimov is reputed to have said:

The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny...'

Whether Asimov said it or not, there is truth to this, at least in my experience. Learning something that is funny—in this context, really, it’s something surprising—does make one curious. Surprise, like awe, is, more or less, learning something that differs from expectations.

Here are some surprising things that might pique your curiosity, the topic of this post.

First, in the scholarly literature, it has been suggested that “curiosity, the desire to know, is a fundamental driver of human behavior.”¹ Nonetheless, in 2009, Kang et al. wrote that “Despite the importance of human curiosity, its psychological and neural underpinnings remain poorly understood.” Subsequently, Kidd and Hayden (2015) wrote: “Curiosity is a basic element of our cognition, but its biological function, mechanisms, and neural underpinning remain poorly understood.” Years later, and bringing us close to the present, Ten et al. (2022) wrote: “Precisely how the curiosity-inducing mechanism operates in biological organisms is poorly understood.”

So I think it’s fair to say that the experts feel that curiosity, while being a fundamental driver of behavior, nonetheless remains “poorly understood.”

Second, the economist in me likes to think that a good way to determine if people like something or hate it is to ask if they will pay for it or, in contrast, would pay not to have to do it. Take number problems. Most people dread taking the math section of the SAT and would, I imagine, pay to avoid it, even if they aren’t applying to colleges and there were no stakes. On the other hand, people pay for Sudoku, which isn’t exactly like math on the SAT, but it sorta kinda feels like a math problem. So that’s… funny. One might make the very same point about word problems. The verbal SAT is no fun, but people pay to have access to Spelling Bee, Connections, and Wordle, to say nothing of the crossword (about which I say more than nothing, below).

Third, I recently came back from a visit to northern New Jersey and was stopped in traffic for 15 minutes. This in itself is neither funny ha-ha nor funny strange, but what is strange, I would argue, is that there were no lanes blocked by the accident, which was on the shoulder on the other side of the Turnpike. Drivers paused to look at the carnage across the median, satisfying their curiosity at the cost of both my time and theirs. At the same time, what should we make of people who avoid, say, finding out who won a soccer match because they want to watch it themselves, or more seriously, people who avoid getting medical tests done that might change their behavior?

So, on the one hand, people seem to pay a (time) cost—and impose one on others—to gather information (about an accident) that isn’t relevant to them. On the other hand, people sometimes go out of their way to avoid information that they seem to want (the winner of the game, a medical test result) and, in some cases, would be useful. In short, people seem curious about stuff that doesn’t and can’t affect them and oddly incurious about stuff that certainly can.

That’s funny.

Curiosity and the Cat

By curiosity, I’m referring to that feeling that you get that you want to know or discover something new.

What might that feeling be measuring?

My sense is that there are two key elements to the measurement which, it will surprise no readers, are to do with the benefits and costs of getting the new piece of information.

On the benefit side, information has, over evolutionary time, had value. Information plays such an important role in so many aspects of our lives it can be easy to miss. Heck, you’re reading this post because you’re curious. Much of the time that we spend these days is consuming information in one form or another, whether that information is written on a web page, heard on a podcast, watched on YouTube, etc.

Information was no less important to our ancestors. What path do the deer use? Where do the lions hang out? Who was flirting with my daughter? Cassandra tried to convey a crucial piece of information—that bringing the horse into the city was a really bad idea—but was ignored, with tremendous consequences for the Trojans. With our big brains, we are the quintessential consumers of information.

Importantly, simply seeking information doesn’t guarantee that we will get it or that the information will be useful: The benefit side is probabilistic. In some cases, we know with very high confidence that with enough time and effort we will be able to discover the information we’re after. For example, barring a misprint in your Sudoku book or the New York Times, there is an answer to each of those puzzles.² The correct information—the numbers in each of the little boxes—can be obtained.

That’s not always going to be the case. You might slow down to a crawl on the freeway only to be confronted with a screen preventing you from seeing the carnage. You might relentlessly track the elusive Siberian Tiger, only to be forced to give up when darkness falls. Similarly, you might bend your ear to the wall, hoping to hear the incriminating confession, only to be thwarted by whispering.

So, whatever the benefit of the information you’re after, you have to multiply that by the probability you’ll get it. In some cases, the probability is near certainty, but in many cases it won’t be.

Then there is the cost side. Discovering information will require at least some time and some sort of effort. These are primarily opportunity costs, since there are always other things that you can do with your time and effort.

In some sense, then, curiosity is measuring the benefit of gaining new information times the probability of getting it, less the cost of the search, which varies depending on what else one might be doing:

              Curiosity ~ (benefit of information) * p(obtaining information) - cost

Is Ignorance Bliss?

The question of why people avoid getting medical information is a thorny one. Here are two ways to think about it, neither of which might be right.

The first way is to do with the fact that humans are peculiarly good at thinking about the future. With our big forebrains, we can plan, which is very useful when you’re packing for your big camping trip.

One consequence of this is that we can forecast what is likely to make us happy and what is likely to make us sad. Normally, this is all to the good because we can use these predictions to make good choices about our happy future selves. These projections are why we work out, work hard, save money, and that sort of thing.

At the same time, we can use our fancy forebrains to avoid information that would be useful but unpleasant. The result of a medical test might well be in that category. So we’re managing our future happiness in the medium term³—finding out the test result—even if getting the information would be useful in the longer term, taking appropriate medical steps, for example, to address the condition.

The second reason is to do with the fact that we are social creatures and the social world—other people—treat us differently depending on certain kinds of information. To put it starkly, we have limited time for friendships and so each of us would rather cultivate friendships with people who are going to be around long enough to be valuable allies. This fact means that discovering, for example, that I have a terminal illness is not just unpleasant: it might well mean that I lose friendships. Avoiding information that makes us less valuable is, then, a reasonable strategy because that information might come to be known. It can’t be if I don’t have it in the first place.

Neither of those two ideas explains why people try to avoid learning who won the Eagles/Cowboys game or keep away from SPOILERS. There is something about the way that we satisfy our curiosity that seems to matter a great deal. I’ll leave that for a later post.

Optimal Information Foraging Theory

Kidd et al. (2015) describe the results of some research by my old friend Colin Camerer and colleagues this way:

They found that curiosity about the answer to a trivia question is a U-shaped function of confidence about knowing that answer. Decision-makers were least curious when they had no clue about the answer and when they were extremely confident. They were most curious when they had some idea about the answer but lacked confidence. Under these circumstances, the compulsion to know the answer was so great that they were even willing to pay for the information even though curiosity could have been be sated for free after the session.

Consider the result in the context of which New York Times crossword puzzle you do. The puzzles get harder from Monday on through the week. Some people don’t bother with Monday’s puzzle because it’s too easy; many people don’t bother with Friday’s because it’s too hard.

There is a Goldilocks level of difficulty that piques our curiosity. If the information is too easy to get, then we don’t bother. There are better ways to spend our time. If the information is too hard to get, again we don’t bother, for the same reason. But if the time and effort to get some new piece of information is just right, then we indulge our curiosity, read the next clue in the puzzle, and figure out the letters that go there.

Secrets and Stakes

Here, then, is how I view curiosity.

First, information is valuable. From an evolutionary perspective, information related to very big fitness stakes is especially valuable. This includes information about who has died, who has had sex, who has committed some moral violation, and so forth. We’re so keen to gather this information that we seek it even when the people involved don’t affect us—as in the accident case—and when it’s not even about real people, as in the case of murder mysteries and other works of fiction. Why do we consume so much information about people who never existed? Our evolved curiosity system is telling us there is important fitness information here! This idea helps to explain why fiction is so often about high stakes events. Story arcs with love, death, sex, and crime feed our appetite for new fitness-relevant information about others. (I argued this about country music songs as well.)

Second, not all information is created equal. Often, information is valuable to the extent it is exclusive. Ask any inside trader why. A good cue to how many others have the information is how hard it is for you to get. If it’s easy, others can get it, and the value diminishes. This helps to explain why we don’t bother with easy crossword puzzles. There is information to be had—the correct letters that go in the boxes—but if it’s easy, then it’s not valuable.

Third, there are costs to seeking information. One cost is the opportunity cost, what else you could be doing. When I was a kid, I once read the phone book in a hotel room during a family trip. It was a rare moment when there was really not much else that occurred to me to do. With the opportunity cost low enough, finding out the names of the Abbotts and the Abrams living in Miami Dade seemed like a reasonable way to spend my time until my parents got back. Some information will be so costly to get in terms of time and effort—the Friday Times puzzle—that it’s just not worth it. Finally, there is the cost alluded to above: some information can actually harm social relationships if fair weather friends desert people who find out that hard times are ahead.

It’s worth bearing in mind that just because we are curious, we don’t necessarily always act on it. Sure, you might say, oh look, a cave, I wonder what’s inside,⁴ but no way you’re getting me in there. The motivation to learn new information can be short-circuited by other motives, including avoiding potential danger.

Curiosity really is a “fundamental driver” of human behavior. You got to the end of this piece because you were curious about where it was going. I hope that your curiosity was satisfied to some extent and, more importantly, you’re curious enough to know what comes next that you’ll subscribe!

REFERENCES AND FURTHER READING

Gopnik, A. (2020). Childhood as a solution to explore–exploit tensions. Philosophical Transactions of the Royal Society B, 375(1803), 20190502.

Gottlieb, J., & Oudeyer, P. Y. (2018). Towards a neuroscience of active sampling and curiosity. Nature Reviews Neuroscience, 19(12), 758-770.

Hsiung, A., Poh, J. H., Huettel, S. A., & Adcock, R. A. (2023). Curiosity evolves as information unfolds. Proceedings of the National Academy of Sciences, 120(43), e2301974120.

Kang, M.J., Hsu, M., Krajbich, I.M., Loewenstein, G., McClure, S.M., Wang, J.T.Y., and Camerer, C.F. (2009). The wick in the candle of learning: epistemic curiosity activates reward circuitry and enhances memory. Psychol. Sci. 20, 963–973.

Kidd, C., & Hayden, B. Y. (2015). The psychology and neuroscience of curiosity. Neuron, 88(3), 449-460.

Kurzban, R. (2012). Cheatin'hearts & loaded guns: The high fitness stakes of country music lyrics. Review of General Psychology, 16(2), 187-191.

Oudeyer, P. Y., & Smith, L. B. (2016). How evolution may work through curiosity‐driven developmental process. Topics in Cognitive Science, 8(2), 492-502.

Sharot, T., & Sunstein, C. R. (2020). How people decide what they want to know. Nature Human Behaviour, 4(1), 14-19.

Ten, A., Oudeyer, P. Y., & Moulin-Frier, C. (2022). Curiosity-driven exploration. The Drive for Knowledge: The Science of Human Information Seeking. Available at: https://inria.hal.science/hal-03447896/file/Ten2022Curiosity-driven.pdf

1. Hsiung et al., 2023

2. Sometimes the Times gets tricky and there is more than one answer, but that’s an exception.

3. Sharot and Sunstein (2020) distinguish among motives when it comes to curiosity, breaking it into three. There is the instrumental value of information, which is useful for decision-making, the hedonic value, how much information will make us happy, and the cognitive value, how much information aids understanding. It seems to me that the cognitive value is often either useful or happy-making, so I think two categories suffice.  

4. This is a reference to Skyrim, for those in the know. Wink.