The Greatest Graphs in History

The Greatest Graphs in History

In 1736, Leonard Euhler created what’s considered the first example of graph theory, when he identified the solution to the Seven Bridges of Königsberg problem. Since then, graphs have recorded and accentuated some of history’s most significant events; from wars to epidemics. Even a quick google search unearths a plethora of examples. While there is plenty to choose from, what is the greatest graph in history?

To answer this question, we start with 3 charts, considered by many as among the most important in history:

Each of these graphs represent a different genre (war, disease, and economics in that order) but all of them were ground-breaking for their time and told a clear and compelling story using data. But which of these graphs is the greatest? From our perspective, John Snow’s chart of the London cholera outbreak best represents the power of data visualization because it:

  1. captured a complex set of metrics in one view (# deaths, relative comparison of households, proximity to water pumps etc.)
  2. used a chart type that pulled together all the relevant data with the right context (impact of water pump location on household death)
  3. highlighted a cause-effect relationship without any complex math or statistics (house holds closest to the water pumps suffered greater # of deaths)
  4. provided a practical future solution to a current real world problem (shutting down of water pumps to limit cholera spread), and ultimately
  5. saved an untold number of lives (once the city shut down the water pumps, the outbreak subsided)

The first instance of “flatten the curve” can be found in a CDC paper published in 2007. It suggested simple interventions like social distancing and keeping kids home from school in order to slow the spread of a disease so that the healthcare system could keep up. The chart was first popularized in the Covid era by the economist which published a briefing in Feb 2020, advocating for strategies to mitigate the spread of disease.

No one at the CDC has been able to identify the author of the original “flatten the curve” chart. But regardless of its authorship, this chart has already proved invaluable in many ways:

  1. as an essential tool to educate the public and encourage compliance with social distancing guidelines
  2. as a way to monitor localities to evaluate disease preparedness
  3. as a framework for governments to issue and revoke stay at home guidelines

There is no doubt future historians and math enthusiasts will add the Covid-19 chart to the top of their list for the most famous charts in history. Whether John Snow’s cholera chart or the CDC’s Covid chart, they are not just great examples of the power of data-driven storytelling. They are also the perfect time capsule of their era, capturing the defining issue of their times in a powerful way and saving thousands of lives in the process.