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The other day, I walked two blocks to visit a friend. We live in a small town in Costa Rica, on dirt roads. Along the route, I saw nails, screws, and wire littering the little road heading east. I had just driven from her house to mine, and wondered how many nails my car had picked up. I went to check and from just one trip, there were two large nails in my tires.
The next morning, I went outside with a metal detector and began to sweep the neighborhood; I simply cannot stand nails in the road. I love and keep horses and all horsepeople know that a single puncture from a nail can kill a horse, so most horsepeople scan the ground habitually. While I found 20 nails on my street and 10 on the street to my friend's house going south, there were thousands on the street heading east. I kid you not.
I stood alone in the road with my metal detector and a bucket, picking up anything sharp and magnetic. At first, I was alone, but gradually a crowd gathered around me. One guy asked what I was doing. I said, it was pretty obvious, I was cleaning the road. I asked how so much metal had been dumped on it. About a year ago, he said, a construction truck (that has been building a condo project) had dumped garbage in the road, and the garbage was full of nails.
A year ago? I was incredulous. He began to pick up nails with me. Then a couple came by, and then four more curious people came along, and soon the street was full of people picking up nails and my bucket was full. One of the men carried my bucket home, and said the metal could be recycled. We completed only half the road, but nobody has finished the clean-up since.
Here is my question: Why on earth did the people who live on that street tolerate thousands of rusty nails on the road? For a year! Lenin said, "Ask Who? Whom?" Who stood to benefit from leaving the nails? I cannot figure this out, because anyone with a car or motorcycle or bicycle or dog or horse would be at risk. The nails even had value, because they are recyclable. As far as I can see, nobody, including the construction company that dumped the nails, stood to benefit by leaving them on the road. My car got two punctures from just one trip on that road. The people who live there must have experienced worse. Nobody benefited, yet nobody took the time to pick the nails up. Nobody asked the contractor to clean up the mess his truck had made. Why?
When posing such social dilemmas, sociobiologists like myself think in terms of game theory. This situation is actually a variation on the famous tragedy of the commons, first pointed out by ecologist Garrett Hardin in 1968. In the original version, people were inclined to take what they could, selfishly, from a common resource, and as a result, everyone was worse off. In the case of the nail-strewn road, everyone had been disinclined to do his or her part (perhaps fearing that each would be a sucker if no one else pitched in), and as a result, everyone once again was worse off!
To some extent, plain laziness may have kept people from maximizing their potential gains. Perhaps one can define laziness as a calculation of greater short-term benefit (doing nothing) than long-term gain (safer roads). Nobody picked up the nails because:
a) Nobody wanted to claim responsibility for dropping them there in the first place and
b) Nobody wanted to take the time to clean it up, especially because no one else would likely pitch in.
So why, then, did my behavior turn out such a crowd? Maybe it broke through the laziness, because people could see that I was cleaning the road, even though it wasn't even my street. Maybe it reassured those who had been holding back, that in fact they wouldn't be the only ones to contribute. Perhaps it made potential laggards feel guilty. In any event, my altruism was actually selfishness; I want to drive to my friend's house without getting a flat tire. The result was a recalculation of costs and benefits by the neighborhood.
Similar instances of miscalculation and blindness must occur to each of us every day. The farther away the cost of doing nothing, the easier it is to ignore that cost. Consider global warming. I use carbon to drive and to fly, knowing that eventually global warming will be a catastrophe, but at the moment it is easier to drive than to bike. Or what about plastic bags? I know they are bad for the environment, but they help preserve my leftovers and reduce the number of visits I make to the grocery. The nails in the road are an example of a "social dilemma," in which nobody wants to be a sucker, cleaning up the road when others will benefit, and everybody is punished by mutual defection, ignoring the problem and getting flat tires.
This is the story with many environmental problems, but I have rarely witnessed it as clearly as here in Costa Rica. Is it the Tico culture? (Costa Ricans call themselves Ticos with pride.) Is it a tropical phenomenon? Many tropical countries seem less tidy than those in the north; I have no idea why. Why didn't people just sue the contractor? Well, they could have, it is easy to file a denuncia or lawsuit, one doesn't even need a lawyer to do it. But nobody did. I just don't have a good answer. All I know is that when I took my bucket and metal detector, and started the clean up, others joined in quickly. So, this shows that one person can make a difference!
As the song from Les Mis goes, "Look Down! Look Down!" And "Clean up! Clean up!"
