Quick! Draw a coffee cup. Or sketch a dog. Or a car. Chances are, if you ask someone else to draw the same object, they'll sketch it from the same angle you do. This is called canonical perspective, and it has an effect on everything from your mental image catalog to the icons on your computer right now.
I have a set rule to never do anything a psychologist asked me to do. You never know when they're going to make you think that you committed murder. So if I had been approached by three of them and asked to draw a coffee cup, I probably would have made a wild stab at them with my pen and run. If I had participated - like one of the many people from all around the world who were asked to draw a coffee cup by Stephen Palmer, Eleanor Rosch, and Paul Chase - I would probably have drawn something like the image of the coffee cups below. Granted, there are only so many ways you can draw a coffee cup, and some people interpret the cup as more bowl-like or more narrow and upstanding. But there are numerous angles from which to depict a cup, and every drawing uses the exact same one. Almost all the cups are seen, by the viewer, from above and slightly angled so the nearest edge is lowered. Even the one large drawing at the top right, which seems entirely in profile, gives itself away by making the rim of the cup an oval instead of a line. We're seeing the cup from above, and, for the most part, from the side.
The researchers went on to test if there was this kind of uniformity in our conception of any other objects. They presented people with pictures of the same object from many different angles. For example, they had people rate the "goodness" of a series of pictures of a horse. Some were taken from directly above the horse, some from directly below, some from the front, back, and sides. Overall, people felt that a picture taken from slightly above and at an approximately forty-five degree angle to the direct front of the horse, was best. This was roughly the same preferred angle as the cup. It was the angle that was preferred for most objects. Even when people were sent off to take their own photos of things, and those photos were judged by yet another independent group of people, both favored that angle, whether this was usually how they saw the object or not.
Scientists believe that the precisely angled perspective is preferred because it allows us to look at the largest variety of surfaces. Looking a horse straight-on blocks out the sides and the back legs. Looking at it in profile blocks out one half of the horse. Although no one was unable to identify the objects in the photos, they strongly preferred pictures that gave the largest variety of information about the different surfaces of the object.
Or did they? These studies were done in 1981, well after the advent of a camera, when most people would have seen these objects presented in media as well as in their everyday life. Consider how many times you've seen an airplane in a movie, and what angle it's shot from. For that matter, how many times have you seen an ad for coffee with a cup angled in that precise way?
Since the original canonical perspective study, experiments have been done which expose people to novel objects in order to see if they'll automatically prefer any special perspective. Some of these experiments do show that people will just get used to whatever angle they're shown most often, and come to be most familiar with the object from that perspective. So this innate preference might just have been programmed into us.
Then again, other experiments show that people will naturally try to work to certain visual standards. People asked to draw certain objects will pick the objects, the number of objects shown, and the size of the overall drawing depending on the paper size that they're given. People asked to copy certain drawings will make consistent mistakes in their approximations. We might naturally organize our visual world a certain way, trying to always think of things in a way that will give us the most information about an object. Many think that this is why computer icons, which need to convey the most information in the least amount of space, are shown from the above-and-at-an-angle canonical perspective. It's the angle that makes the object immediately recognizable to us.
So are our eyes, and our brains, agents of conformity, or just efficient processors of information? This might help. Actually go ahead and sketch a coffee cup. I'll wait.
For those of you who indulged me and drew the coffee cup, who put the handle on the right, and who put the handle on the left? And, of those of you who put the handle on the left, are you left-handed? If so, maybe you're drawing what you actually see every day - instead of an icon that's shown to you.
Top Image: SXC