By Dr Jon Minton, University of Glasgow
…The Great War tended to be much more deadly than World War Two, killing a greater proportion of those who fought; and secondly, and most tragically, that the Great War, in combination with the influenza pandemic that swept through Europe in 1918, appears to have killed and weakened many people who were not even born at the time, but instead in its wake.
What would the world look like if we could see time as space, stretching out into the distance, the near future and near past visible to us as nearby objects, ancient history and the distant future just specks on the horizon? In the novel Slaughterhouse Five, Kurt Vonnegut conjured up an alien species, the Tralfamadorians, for whom time was simply another dimension that could be seen like any other. For them, the events of birth and death were not surprises, eliciting joy and fear as they did in people, but were instead simply features in a four dimensional spatiotemporal landscape. Because of their perspective, the aliens were (and are, and will be) fatalistic, not horrified as people are by war or disease or famine, as such events are simply part of the scenery.
Slaughterhouse Five has been critiqued and criticised as a work of quietism, the aliens a narrative device, their fatalism in fact Vonnegut’s fatalism, the protagonist’s experience of witnessing the firebombing of Dresden channelling his own experience of this event. In this interpretation, the novel grew out of psychological scar, with Vonnegut wounded by witnessing, first hand, the enormity of advanced warfare in the twentieth century. The wound suffered as a young man, the scar carried by the author into his dotage in the new millennium.
Both of these notions – seeing time as space; the invisible scars that people carry with them through time – have resonated strongly with me as an accidental demographer. Three years ago, I discovered an old way of looking at demographic data which involves laying out the data in a format known as a Lexis surface, developed by the German social scientist Willhelm Lexis in the nineteenth century. In a Lexis surface, time is space, demarcating one dimension on a rectangular canvas. The other dimension along the canvas is age: newborns at one end of the axis, the elderly at the other. For each combination of an age and a year there is a value; for most of my visualisations, the risk of dying within the next year. The canvas of the Lexis surface is not flat, but varies in height throughout. These heights are in proportion to the values, so something twice as high as something else implies a risk of death that is twice as great. Within this representation, our lives travel in diagonal grooves: we age one year per year, with the twenty year olds in 1916 becoming twenty one year olds in 1917.
The challenge with Lexis surfaces is in representing something that is three dimensional on a two dimensional page or screen. In a pair of blog entries for the Oxford University Press (The Good News, The Bad News), I described how these Lexis surfaces can be rendered as orienteering maps, using contour lines to provide an impression of how annual mortality risks have varied with age and time. Steep changes over sections of the surface are represented by many contour lines clustered closely together, shallow changes by lines spaced further apart, and when following a line the height, and so risk, never changes. These two blog entries went into some detail, decoding the maps to reveal both the good and the bad news about demography that can be read from them.
The bad news could be divided into the obvious – the World Wars killed many people who fought in them – and the less obvious – the World Wars killed many people who didn’t fight in them. The two least obvious facts revealed by the Lexis surfaces, and the reason for this blog entry being here, are firstly that, despite the weaponry being less advanced, the Great War tended to be much more deadly than World War Two, killing a greater proportion of those who fought; and secondly, and most tragically, that the Great War, in combination with the influenza pandemic that swept through Europe in 1918, appears to have killed and weakened many people who were not even born at the time, but instead in its wake. Within the Lexis surfaces, this pattern reveals itself as a diagonal scar in the demographic records, following a particularly unlucky cohort born near the end of the Great War. What this scar shows is that this cohort experienced higher risks of death at all ages compared with people born a few years before or later. For this cohort, as a result of the scarring, life was always a little riskier.
Since writing the OUP blog, I have started to look at other ways of rendering the Lexis surface that require less effort to decode and understand, where the impact and impression made by the scars and features of the demographic landscape is more immediate and visceral. Currently my plan is to turn some of these Lexis landscapes into physical objects using 3D printing technology, producing statistical sculptures that can be touched rather than just looked at from behind a screen. An example of such a rendering is below. The bottom left hand corner denotes newborns born soon after the establishment of West Germany, and the opposite corner is of 80 year olds in the early 1990s. Even though there was no West Germany at the time of the Great War, its scarring effects are still visible in the demographic records, connecting East Germany and West Germany even when an Iron Curtain kept them apart.
The demographic records of Europe showed that the effects of the Great War were still being felt at the turn of the twenty first century. The bodies of the Great War birth cohort could not forget, and nor should we.
Dr Jon Minton is a Research Fellow in the Urban Segregation and Inequality strand of the Applied Quantitative Methods Network (AQMeN). He is based in Urban Studies within the School of Social and Political Sciences at the University of Glasgow.
His recent academic publications on demographic visualisation include:
Minton, Vanderbloemen, Dorling (2013), ‘Visualising Europe’s Demographic Scars using Coplots and Contour Plots‘, International Journal of Epidemiology.
Minton (2013), ‘Logs, Lifelines and Lie Factors‘, Environment and Planning A.
Minton (2014), ‘Real Geographies and Virtual Landscapes: Exploring the Influence of Place and Space on Mortality lexis Surfaces using Shaded Contour Plots‘, Spatial and Spatio-temporal Epidemiology.
He has taught workshops on data visualisation principles, and will be leading a two-day AQMeN data visualisation workshop in Glasgow on 22 and 23 October. This workshop will include the demographic visualisation discussed here. Further details of this event are available here.