Monkey See, Monkey Do What could be easier than matching the length of two lines? Imagine you were asked to participate in a basic vision test. In front of you is a pair of cards. On the left card is a line. And on the right card are three comparison lines, A, B, and C. Your job is simple. Just pick the line on the right that is the same length as the target line on the left card. Decide whether line A, line B, or line C is the same length as the target line. Should be easy, right? Now let’s add one more wrinkle. Rather than doing the experiment alone, you participate with a group of your peers. You show up at a nondescript building on a university campus, and walk up a flight of stairs to room B7. You see that six other people are already seated around three sides of a square table, so you grab the last remaining chair, the second from the end. The experimenter gives the instructions. He reiterates that your job is to pick the line on the right that is most similar in length to the one on the left.
