Enjoying the Natural History Museum yesterday, I came across this exhibit somewhere in the geology section:
The exhibit is a serious of columns, which you pass from right to left. The penultimate column is to illustrate the idea of ice, and you’re invited by a palm shape to put your palm to the column (which is indeed cold). The interesting thing is the final column, which is meant to illustrate gravity somehow (it was broken yesterday, so I don’t know how it is supposed to do this). Notice how the metal around the IVY of gravity is worn away. None of the other columns had this. Obviously hundreds of visitors a day are drawn to this exhibit, press their palms to the ICE column and then go on to touch, in exactly the same way, the GRAVITY column even though this isn’t part of the way they are supposed to interact with the exhibit.
Psychologists know that what people have done before is the best predictor of what they will do in the future. Whole industries are devoted to helping us establish, or break, habits. This exhibit on geological forces illustrates how easily some behavioural precedents can be set. We love touching things, and although we aren’t meant to, permission to do it once is all that is required to set off an immediate repetition of the behaviour.
Mind Hacks 
Interesting observation Tom. When it comes to predicting human behavior, just ask yourself what you would do in the same situation. The majority of people will make the same choices as you. It’s only deviants and innovators that fail to follow the pack.
It’s hard to tell from the picture, but I wonder if the “ity” part of the column rotates, pushing up the “grav” portion. Gravity will then pull the “grav” back down, thereby illustrating the concept. The warn area is where people are pushing that portion of the column to twist it, then.
Yes, it depends on how that column works. But this sort of ‘momentum’ in action has become a fairly hot topic recently, it pops up in a variety of tasks. I’ve run a couple of studies on this in the past, and the lit review at the time showed people were starting to see it all over.
These types of hysteresis effects are evidence of the kind of non-linear dynamical systems involved in the production of action.
Even if the reason for the mark is not the one you think, your observation is spot on. That’s what people do in many situations: if they don’t know how something works then they’ll just repeat the method they used last, especially if it also made them feel good.
And touching things IS great.