Noisy Gorillas and Silent Evidence

A little girl pounds her chest in front of the gorilla habitat at the Henry Doorly Zoo in Omaha. The alpha male silver-back charges the window and hits it hard enough to crack the inside layer of the three-layered glass. It is an impressive display that makes the news and fills up a slow day on social media outlets.

I am fascinated by the pronouncements of all the "experts" in the wake of this (non) event. This is, one part-time pundit declares, the result of years of harassment by hundreds of mean-spirited little kids. The male finally had enough and reacted. I must wonder how many other small children (and the adults they were imitating) did precisely the same thing with no ill effects.

Another humble analyst proclaims that this is the result of taking these wonderful wild creatures out of their natural environment and subjecting them to the rigors of captivity. The alpha finally "snapped" and took out his frustration on the window and the little girl. I am assuming that this conclusion is drawn from post-event debriefing with the alpha male and other members of the oppressed local gorilla community.

Of course, it may well be that the gorillas suffer from their captivity. But again, where is the evidence that such stress has produced this particular incident? It is easy to see the things you already expect to see.

Yet others are sure that this result was completely unanticipated by the management and keepers at the zoo. Of course, this is harder to sustain in light of the fact that the glass was part of a triply redundant system that seems to have been designed for precisely such an eventuality. That small detail aside, we have calls for a thorough-going re-evaluation of the system for maintaining the gorilla enclosure.

Nassim Taleb reminds us that we are often victims of the "Silent Evidence" problem. This blind spot leads us to draw faulty conclusions from inadequate evidence. We see a problem in front of us. We are highly sensitive to that problem--a big bang and cracked glass will get a person's attention. We are not sensitive to all the times when this didn't happen. We have to think hard to put the event in a realistic context because that requires us to imagine non-events.

That's not our strong suit as humans. Thinking hard takes lots of work. Of course, without ignorance of the Silent Evidence problem, social media outlets would certainly be quieter and less dramatic places.

Instead, we over-read the specific event in front of us. That over-reading typically leads to over-reacting. And over-reacting usually has negative consequences that may relieve our stress but that rarely make the problem better. And we under-read the times that the event didn't happen. That under-reading means that we are insensitive to the things that actually work in our lives and in the world. And so we tend to under-support, under-fund, and under-appreciate these positive things.

For example, we will notice the one time our spouse might forget to take out the trash. We tend not to put that into the context of all the times that the chore actually got accomplished. So we over-react to the immediate stimulus, have a fight and spend some unhappy moments. We could choose to remember the positive side of the equation and have some happy moments instead. It is a measure of our predictable irrationality (thanks as always to Dan Ariely) that we so often choose the path to unhappiness.

Thank you, staff, keepers, architects, managers and supporters of Henry Doorly Zoo for building an enclosure that managed this unusual event. It would be best if the rest of us spend our energy gathering information and get less exercise jumping to after the fact conclusions.