Why so visual?
One thing I often notice when working with web designers is that they focus mostly on visual aspects. I have discussed before that the web is not a visual medium. But in this article I want to go deeper into the topic of visuality itself.
For some reason, we treat sight special. We say "I see" when we really mean "I understand". Bret Victor even claims that "People understand what they can see". Why is that?
First, it is important to note that sight is especially well developed in humans compared to other mammals. Dogs for example have an advanced sense of smell instead.
I also think you can put our senses into three rough categories: Smell and hearing are great for getting a general impression of your surrounding. They can warn you of dangers (e.g. smell of gas or loud noises). They are not as good to focus on something. Touch and taste on the other hand are very close to your body. They can be used to get detailed impressions (e.g. petting a hamster), but there is also a certain risk (e.g. getting punched in the face).
Sight in some way combines the benefits of both of the first two categories: It works at safe distance and it can be used for both focusing on something or scanning (e.g. a room or document).
The third reason why I think that sight is especially useful for us humans is that it is easy to create visual records. Drawings are one of the oldest form of human expression. Even though we also have some ancient stories, that required to pass them on orally from generation to generation. Writing them down was ultimately the better way to record information. (Today, we can also record sounds. But that is a comparatively recent invention.)
Maybe comparing sight to other senses is not the right approach: I think that what Bret Victor enjoys about seeing a diagram is that it is more intuitive to understand than a text with the same information.
Text can be ingested with different senses, mostly sight and hearing (but also touch). This is why accessibility people like it so much.
But text is also linear. A story can communicate a great deal of emotion, but only if you read it in order. If you were to read the sentences in reverse, the effect would be totally lost. You also have to read through the whole thing to understand the emotional depth. A graphic on the other hand can communicate all those emotions on first sight, e.g. by using certain colors.
This gives graphics a lot of power. But with great power comes great responsibility. There are countless examples of misleading or even manipulative graphics.
Even though I believe that most designers act responsibly, I feel that some trends are worrisome. Today it is hard to find a complicated text that is not "lightened up" by some image. I fear that these graphics are intuitive to a point where you believe to understand more than actually understanding.
After reading a lot about the topic I now have a better understanding of why visuals are so important in web design. But I still think that we should be critical about our use of it: Does a graphic aid understanding or manipulate? And who is excluded from what information? These are questions we should ask whenever dealing with graphics.