Drucker prefaces her second chapter, "Interpreting Visualization :: Visualizing Interpretation," with the concept that every visualization can be categorized as either representations or knowledge generators. The difference is representations are of information that is already known, whereas knowledge generators create new information through their use. This is important context as we read through the history and analysis of visualizations related to time, space, and many other subjects in this chapter.
Since this was a bit of a lengthy chapter, I'll highlight my top insights across Drucker's 8 sections.
Time Keeping
One of the most important pieces of time keeping, is that it's based on a shared cultural understanding. Often rooted in religious markers in time (pre / post Messiah, etc.), societies based time keeping on events that everyone in their society could perceive or reference. One of the most critical points here is that "the shape of temporality is an expression of belief, not a chart of standard metrics" (p. 76). We all experience time in different ways based on how we're feeling. A slow line, a boring movie, a fun party will all feel different even if they span the same length based on our emotional disposition. Interestingly, we can feel an hour even though it's not based on any natural law like a day or year is. That's an example of another shared cultural understanding. The Earth has no concept of an hour, but yet we as humans do.
Space-making
In order to provide context, Drucker informs us that maps have two distinct purposes: to navigate and to communicate ownership. In early maps, the ability to "project a multidimensional form from a flat drawing" (p. 78) was a significant milestone technical achievement, in reference to Babylonian clay property map. This got me thinking about our current maps, specifically the mercator projection which distorts and exaggerates landmasses in order to accurately translate directional/navigation information. "The constructed experience of space cannot be presented in standard cartography any more than the variable concepts of temporality be charted on a standard timeline. (p. 82) To me, that's a very profound and accurate insight. While looking at a map, we feel it is an accurate representation of real life, there's always going to be some level of abstraction necessary even if users do not consciously perceive it that way.
Administration and record-keeping
By far, the most interesting point made here is in regards to the visualization of tabular data forms. Specifically, that is may "be the first fully diagrammatic human activity...which that spacial ordering has no analogical reference or prior existence." (p. 86) I had never thought about this before but it makes sense and it's extremely interesting to consider. Everything graphic up until tabular data forms had been an abstraction of real life in some way (time, space, etc.) but the data tables we see every day were created uniquely for a graphic purpose. The core design principles of alignment and typography are proven here. And from there, we go on to get graph paper, grids, and sophisticated layout structure intended for optimal human-readable form often used in administrative tasks.
Trees of knowledge
A tree is an allegorical symbol with roots in many cultures and religions, like the tree of life. It makes sense that we use trees to model databases and other complex data structures like a family tree (probably the most direct parallel). Trees are a great example of knowledge generators because the spatial arrangement of the branches, leaves, etc. produce meaning in itself – not just in the nodes/branches.
Knowledge Generators
As mentioned before, knowledge generators create meaning through combination and spatial positioning. An example of this is the Kabbalah Sephirotic Tree that teaches the nine orders of angels. This is a distinct diagrammatic example of a spiritual graphic. To gain spiritual knowledge, "the mind must move through its structure to engage." (p. 111) therefore, creating new meaning through combinatoric and spacial features.
Additionally, the Venn diagram is another knowledge generator; however, it's worth pointing out that the circular form used to bound items inside, doesn't mean anything except to communicate the category those items live. In other words, the fact that it's a circle, doesn't matter. It's not a representation of anything real. It could just as easily be a square.
Dynamic Systems
Visualizing weather, an event that marks state changes, is an example of a dynamic system – often difficult to visualize in a static graphic format. Additionally, representing tides and currents on top of cartography (like when we see the hot air gusts over the map of the USA on tv) were first mapped in 1686 by Edmond Halley. The ability to show wind gusts, atmospheric changes, thunderstorms, etc. all depict process and change in a dynamic system on a static graphic. Once the ability to generate motion graphics because possible, we could visualize "spacial-temporal illusions" that make mapping things like weather events conceptually easier to understand, even if they are mathematically inaccurate.
Visualizing Uncertainty
"Realist approaches depend above all upon an idea that phenomena are observer-independent and can be categorized as data." (p. 125) I appreciate Drucker's sentiment here, that data collection and observation are not the same thing. The act of collecting data always needs to be evaluated as an observer interpretation by the collector and not the representation of raw facts. Restated by Drucker later, "the fundamental parameters of chart production, are already interpreted expressions." (p. 129) When people look at a bar chart or pie chart, they don't question it and assume they're looking at unfiltered data even if there are gaps in the data, but this implicit trust needs to be questioned, "all data is capta."
Humanistic Methods
This chapter, towards the end of the section, gives us a bit more insight into Drucker's personal feelings of capturing and visualizing data. In fact, we're told to suspend the conventional standards of graphical structure in favor of a humanistic interpretation...a push to do something different even if it's not perfectly legible or follow the rigid rulesets. There's an emphasis on not collecting data as unbiased and objective as possible, but to focus that moment of observation and pivot to consider interpretation first. Let yourself be affected by the thing you are observing.
Finally, in the concluding section, we are taught we must focus on the "interplay between a situated and circumstantial viewer and the objects or experiences under examination or interpretation" (p. 136), which I took to mean that there's always a connection between real life and graphic design. Essentially, there's something you're observing in the real world that must be interpreted, recorded, and abstracted to ultimately become a graphical visualization – and it's our responsibility as designers to translate that process to our final design which the viewer only sees.