We don’t attend to everything we see. As Andy Clark has written in Natural Born Cyborgs, our brains don’t bother to create rich inner models of the world. We can’t create such models because there is simply too much information out there for us to process it all. Further, the world is generally available to revisit periodically, so why bother? In other words, we use the world as its own best model–we “cheat” (because we must cheat). But this cheating can be exposed through dramatic experiments. I’ve previously posted on some of those experiments here (by Quirkology).

Here are some additional experiments demonstrating our need to “cheat.” In this experiment, done by Dan Simons and Dan Levin, only 50% of the subjects noticed that the person to whom they were talking had changed. Here are additional demonstrations by Simons, along with a bit of explanation. Here’s a more elaborate write-up on the “door” experiment. And see here. When I use the word “cheat,” I’m being facetious. Our strategy of using the world as an adequate model is one of the many cognitive heuristics we must use in order to survive.

Here is a another good example of “change blindness” for me (I’ll put the answer at the bottom of this post, in case you’d like to try it). This example (and these) were assembled by Ronald Resnick. At this site, he explains that we need to attend in order to see change.

A related topic is our obliviousness to incremental change. That was the subject of my post about the disappearance of tigers. Here are several dramatic demonstrations of our inability to notice gradual changes [watch them in real time; if you don’t notice the changes –I didn’t–grab the “knob” on the progress bar and slide it quickly].

I’ve often considered the moral an political ramification of our limited ability to attend to all of our surroundings. That we focus on some things to the exclusion of others, and that we are limited in our ability to attend to all of our surroundings, makes us susceptible to many bad arguments. This susceptibility is dramatic because we also carry around a prejudice that we have full knowledge (or, at least, adequate knowledge) where ever we go. We are epistemologically cocky, and this makes us vulnerable. We can be led to focus only on some data, to the exclusion of other data. Magicians take good advantage of this tendency. So do some politicians, who lead us to focus only on human differences, rather than the vast number of things humans have in common (Bill Clinton once gave a moving speech on this issue). I’ve long believed that attentional frailties, combined with fatigue and the illusion of adequate knowledge, are the battleground for many moral and political issues.

[Hint: The airplane engine disappears].