THE Covid-19 pandemic has created a situation where many non-scientists are looking intently at graphs, numbers and diagrams. Aside from complex questions such as how to make fair comparisons over time when definitions may have changed (the topic of our last column), the problem of showing the data itself in a fair and clear manner has prompted a great deal of argument.
 
As well as official government graphics, many newspapers and websites have in-house teams who produce their own graphs, updated in real-time. What’s more, individuals on Twitter pass around their own homemade graphs like scientific samizdat. Often they are using the same underlying data but are “visualising” it differently.

For example, whether a graph uses a linear scale or a log scale can change what it looks like, which can lead to different impressions about the severity of the situation. Those making diagrams regarding Covid-19 also need to decide how to show numbers visually; for example, data from scientific experiments has been used by designers to make graphics highlighting droplets drifting over a room after a cough, aiming to make the invisible visible in a “realistic” way.
 
The concept of “data visualisation” may seem recent, but its analysis goes back over a century. One important influence on modern data visualisation was the so-called Isotype School, founded by Otto Neurath. Neurath originally called his system the Vienna Method of Pictorial Statistics.

He felt that even if people were illiterate, they should be informed and educated about societal issues. The fundamental aim was to convey quantitative or procedural information without using words.

He worked in close collaboration with Marie Reidemeister. She was the more talented graphic designer and coined the name Isotype — shorthand for the International System of Typographic Picture Education.

In 1936 they published International Picture Language, a book which set out Isotype’s strict principles. The book featured multiple examples of “picture education.”

For example, there were multiple comparisons between countries, using the now widespread but then revolutionary technique of repeating a unit icon multiple times to represent quantities on a world map (such as populations).

The book also included examples of clear signage as well as diagrams explaining various procedures with stylised humanoid figures, the descendants of which will be familiar to anybody who has bought Ikea furniture and followed the pictorial instructions.

The most important principle of Isotype was that a “teaching-picture” should have an extremely clear main message, and that any unnecessary decorative detail should be removed.

When considering a good diagram, “At the first look you see the most important points, at the second the less important points, at the third the details, at the fourth nothing more — if you see more, [it] is bad.”
 
Isotype had extremely philosophical roots. Earlier in the 1930s, Neurath had been one of the authors of the  manifesto of the Vienna Circle, which set out the case for logical positivism. A chain of philosophical influence links Bertrand Russell, who mentored Ludwig Wittgenstein, whose writings then heavily influenced Neurath.

Interestingly, all three philosophers spent time working on mathematical logic before abandoning it to try and improve what they saw as deficiencies in conventional education.

Russell set up and ran the experimental Beacon Hill School; Wittgenstein taught in a rural village in Austria and published his own children’s dictionary; and Neurath collaborated with Reidemeister to develop Isotype.
 
Along with many others, Neurath and Reidemeister fled the Hague in 1939 to escape Nazism. They were interned on the Isle of Man, along with other non-British citizens, until February 1941.

On release, they married and moved to Oxford. As graphic designers they found plenty of wartime work through the Ministry of Information, producing diagrams for documentaries.
 
It was after the unexpected death of Neurath in 1945 that Reidemeister and the remaining Isotype team moved on to produce a range of science books for children. The books were compelling introductions to scientific ideas, with sparse words included alongside illustrations.

For example, a book about space featured one illustration called The Beginning and End of a Star, which explained how nuclear fusion and gravity interact at the start and end of a star’s life using a cross-section diagram of the forces. This representation has become ubiquitous in science books. 
 
Key to these illustrations was the creativity of Reidemeister as the principal “transformer” — akin to what we’d now call a designer — as otherwise the work would have been in vain. Neurath was aware of this, writing to a friend shortly before his death that “the wit is in the arrangement.”

Reidemeister had to extract the essential facts from a mass of information collected by researchers and interviews with experts and display them in the form of pictures. She saw her role as being “the trustee of the public,” deciding what was worth knowing, how to convey it and how to link it to other knowledge.

Before becoming an apprentice designer she had trained to be a teacher, specialising in mathematics and physics.

She brought a deep familiarity with the subject matter. For example, in 1958, the educational film Inside the Living Cell featured Isotype diagrams about the molecular biology of DNA.

Given that the structure of DNA had only been discovered in 1953, the ability to render it comprehensible to children shows how impressive the achievement of Reidemeister and the rest of the Isotype team was. Modern visualisations still use many of the same elements.
 
Although such work extended Isotype far beyond the “pictorial statistics” idea Neurath originally had, Reidemeister still held fast to the original design principles.

One of these was the rejection of perspective in favour of cross-sections. On one occasion she refused to change her diagram of Piccadilly Station to show trains crossing at an angle, as requested by a publisher, because it contradicted the fundamental principle of Isotype that perspective was to be avoided because it distorted the relative sizes of objects.
 
Although modern data visualisation has more sophisticated tools at its disposal, Isotype is still relevant today. Neurath and Reidemeister recognised that the same underlying data can be shown in a variety of ways, each of which will have a different message.

Many of the Covid-19 graphs in circulation could fairly be described as a form of what statistician David Spiegelhalter calls “number theatre” — their primary message is often to pretend that the government is on top of the situation because it has a shiny graph.

The message conveyed by the numbers themselves may be quite different.