Visualizations need interpretation as a way to grasp the meaning of visual representation. They are complex, and often the process of creation is hidden to the public. Because of this, the following text illustrates a way to read the visual representation of data by analysing the reading in three intervals: detail, visualization, and context. These three different moments make explicit the structure of reading, which will end with the interpretation-the moment in which the observer gets insights and becomes conscious about a personal kind of knowledge. Interpretation, which is composed of personal opinions, is a very important medium to keep the information circulating and to permit an open dialogue with other observers who are reading the same visualization, even in the medical field. In this paper the photography of Luigi Ghirri will illustrate the schematic approach; successively, the three intervals will be exemplified using a medical example, where my parents will be involved in the reading of a blood test. The simple idea is that, through the circulation of opinions and the dialogue, visualization interpretation will foster the creation of a common knowledge and improve the capacity of reading by each single observer.
Luigi Ghirri wrote a book titled How to think in pictures. His way of taking
photographs shows a certain way of thinking; for him photography was something to take
seriously. Among his invaluable lessons, the thought that photography is essentially
an operation of subtraction from the real world stimulated my interest [
The act of reading, performed by the observer in front of a text or an image,
produces a natural consequence that follows two directions, one toward the detail and the
other toward the context. Looking at a photograph, it is clear that someone can
understand something meaningful. This is what Roland Barthes named punctum [
For example, looking at this photograph by Luigi Ghirri (Fig. 2) could bring us to a couple of outcomes. An observer could look at the snow in the photograph—the detail—and think about his childhood when he used to play with friends during the winter—the context. Another observer could look at the red building on the right of the image and recognize the San Cataldo Cemetery by Aldo Rossi and Gianni Braghieri. There is, in addition to the two interpretations, the choice of Luigi Ghirri to hide a large part of the cemetery; as result, the red cube, which is the ossuary building, is subtracted from the other buildings of the cemetery to become a relevant element in the picture.
Thus, the snow and the ossuary are details of the same photograph. Even if both
belongs in the same photograph, they trigger different interpretations: one person
thinks about his childhood, one about the architecture. Moreover, for the
photographer the ossuary represents an element isolated to being part of the pictorial
composition. Two details for three different examples of context.
Photography is just one of the varieties of representation devices used in science,
among these are diagrams, networks, graphs, maps, documents, computer
applications, recordings, data, etc. One possible device corresponds to visualizations. Lev
Manovich employs visualization to indicate ‘situations when quantified data which by
itself is not visual [...] is transformed into a visual representation’ [
Recent studies in Digital Humanities claims that each person has an individual way
of understanding visualizations [
The point is that there is still no method to understand visualizations now, and the
variety of interpretations makes any result unpredictable and unclassifiable [
The schema previously illustrated shifts to visualization, and the intervals become
detail, visualization, context. The visualization substitutes the photography because
interchangeable representation devices are used in science. The schema helps to
consider the act of interpretation at different levels. The detail defines an element of the
image that someone notes for personal interest, the visualization represents data
which people look at—the vision, and the context is the distinctive background that
brings the observer to a subjective interpretation—the visuality. Nevertheless, the
context has blurred edges because it can overlap with other contexts belonging to
different people. That is an important fact because observers can agree on a common
concept, a shared idea, or a controversy. Detail-visualization-context sequence can be
seen as a scale, from the personal view to the collective one, like a visual technology
capable of zooming from the detail to the context, from the particular to the whole—
an instrument to improve comprehension of interpretations. To guess what the Figure
3 would represent, you probably have to refer to the book Cosmic View of Kees Boeke
[
Fig. 3. The zoom effect works on the three levels of interpretation, from the left detail, visualization and context.
Through the zoom each observer moves from details to contexts and vice versa, but
what happens when the different movements of zoom coexist in the same space?
Observers cross each other in the space where the visualization extends itself between
contexts and details, where each interpretation is the terminus of a trajectory [
The point is that images are not immobile objects still in the space, they are free to
move around people [
Once my father did a blood test, a simple examination in order to get information about his medical condition. Sometimes my father could appear to be a hypochondriac; it is not always the case, but at that time he did seem that way. My father went to the hospital, did the blood collection, and then received the results at home after few days. The letter contained an table of the results; each value was within the limits, except one. My father, who for this occasion was very much being a hypochondriac, was seriously worried. He made the week before the doctor’s appointment very stressful for my mother because one value was passed the limit. After one week elapsed, my father went to the following appointment. Once he entered the doctor’s office, he started asking a series of questions—with my mother looking embarrassed. At a certain point the doctor stopped my father and said, “Dear Claudio, your medical condition is extremely good for a man of your age. You’re simply becoming old, and you don’t have to worry about this blood value.” After a while my father was euphoric and felt healthy again, and my mother finally relaxed. 5
In this example, there are three actors: my father, my mother and the doctor. Each of
them sees a different detail in the blood test. My father is concentrated on the value
which exceeds the limits, whereas my mother and the doctor concentrated on the
whole result. However, the discussion between my mother and my father is not
helpful for reaching an agreement and having the same opinion, even if the argument of
my mother is fair. Often opinions do not agree and stay diverged. With the entrance of
a third actor, the doctor, something changes. He has an interpretation similar to my
mother, but, on the contrary, because his opinion is characterized by an authority in
this specialized area of medicine, he consequently creates a different point of view in
the eyes of my father. For this reason, the discussion between my father and the
doctor has a different result—it ends with an agreement. The doctor is able to change the
opinion about the blood test of my father through his knowledge and his position as a
specialist. Possible arguments and tactics during a discussion are multiple, but this is
not the point of this text. What is important is the creation of knowledge, the
modification of opinions, or, in other words, the circulation of interpretation between people.
Contexts have to be fluid, movable and dynamic; discussions are never static, in every
controversy there is a movement of the frontier which limits the two opinions [