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CH 17Systems & finance
History & systems · 26 case files
History and complex-systems investigations.
Disasters, expeditions, markets and public health: how decisions, warnings and conditions combined into historic outcomes.
Backdrop: The New York Stock Exchange trading floor in 2011, a year after the Flash Crash. The crash itself unfolded across electronic markets in minutes. Carol M. Highsmith · Public domain · Wikimedia Commons. Figure: Mary Schapiro. Chair of the US Securities and Exchange Commission, 2009–2012. US Securities and Exchange Commission · Public domain · Wikimedia Commons.
Some outcomes belong to whole systems rather than to one machine: a harbour full of wartime traffic, a city deciding when to close its schools, a market where every algorithm reacts to the others, an expedition whose goal changed beneath it.
These investigations use inquiries, archives and later scholarship. They look at what people knew at the time, which signals reached the right decision-makers, and where the record is still disputed. Hindsight makes many of these choices look obvious; the evidence usually shows why they were not.
- 2 beginner
- 17 intermediate
- 7 advanced
Other fieldsEngineering & technologyScience & discovery
CH 19Environment & history
CH 20History & discovery
The exception beside the pump
John Snow and the Broad Street pump
Soho, 1854: test the pattern against the people it misses
CH 21History & technology
A guess that rules things out
Enigma and the Bombe
Bletchley Park: the machinery behind a testable crib
CH 22History & exploration
When the destination stops mattering
Endurance expedition
Endurance, 1915–1916: revise the mission as the evidence changes
CH 24History & technology
A photograph without film
Kodak’s digital camera prototype
Kodak, 1975: distinguish a working principle from a finished product
CH 35History & technology
The ship that heeled too far
Vasa (ship)
Vasa, 1628: a warship that capsized in Stockholm harbour on her maiden voyage
CH 36Environment & history
The cold summer after Tambora
Mount Tambora eruption (1815)
Tambora, 1815-1816: how far can one eruption explain one cold summer?
CH 37History & exploration
Lead, scurvy and a long winter
Franklin expedition
Franklin expedition, 1845–48: what the evidence says about why it failed
CH 38History & technology
The dam that could not spill
Johnstown Flood
Johnstown Flood, 1889: why the South Fork Dam failed, and what the record can say about responsibility
CH 39Environment & history
A warning that pointed elsewhere
1900 Galveston hurricane
Galveston, 1900: forecasting limits, Weather Bureau warnings and an island city without a seawall
CH 40History & technology
Ice ahead, speed unchanged
RMS Titanic
RMS Titanic, 1912: did the ice warnings, speed and lifeboat provision shape the outcome?
CH 41History & technology
Wrong side of the Narrows
Halifax Explosion
Halifax Harbour, 1917: a munitions ship, a collision and the question of blame
CH 42History & discovery
The parade and the closures
1918 influenza pandemic
US cities, 1918: did the timing of closures and gatherings change how the epidemic hit?
CH 43Environment & history
Drought meets the plough
Dust Bowl
Southern Great Plains, 1930s: did drought alone create the dust storms?
CH 44History & technology
What the film could show
Cuban Missile Crisis
Cuban Missile Crisis, October 1962: what the U-2 photographs could establish, and what they could not
CH 70History & exploration
The tent under the shoulder
Dyatlov Pass deaths (1959)
Dyatlov Pass deaths, 1959: could a small slab avalanche explain the damaged tent and the injuries?
CH 71History & technology
Gears inside the rust
Antikythera mechanism
Antikythera wreck, 1901: how did X-ray CT turn corroded fragments into an astronomical calculator?
CH 72Environment & history
A gas cloud from still water
Lake Nyos gas disaster (1986)
Cameroon, 1986: where did the carbon dioxide come from, and what released it?
CH 73Systems & technology
The computer said the cash was missing
Post Office Horizon scandal
Post Office Horizon, 1999 onward: why was the computer believed when it reported missing money?
CH 74Systems & finance
Safe bonds and a two-day run
Silicon Valley Bank failure (2023)
Silicon Valley Bank, 2023: how did a bank with mostly safe securities fail in two days?
CH 75Systems & technology
Which test was actually run?
Theranos blood testing (2013–2018)
Theranos, 2013–2018: what separates a demonstrated lab test from a claimed one?
CH 76Systems & finance
Returns that were too smooth
Bernard Madoff Ponzi scheme
Bernard Madoff's firm, 1992–2008: what did the numbers show that regulators missed?
CH 77History & technology
Seven handshakes with a satellite
MH370 disappearance (2014)
Malaysia Airlines flight MH370, 2014: where did the satellite data place the aircraft?
CH 78History & technology
Three suspects for a burst tank
Great Boston Molasses Flood (1919)
Boston, 1919: why did a storage tank burst and send a deadly wave through the North End?
CH 79Systems & energy
Why so many plants stopped at once
Texas grid freeze (2021)
The Texas grid, 2021: which failures pushed the system to the edge of collapse?
From the journal
Read the method behind these cases.
- Confounding: why two groups can differ for other reasonsComparing groups can reveal causes or mislead about them. Learn how confounders, natural experiments and seasonal patterns change what a comparison shows.
- Warnings that did not land: when signals fail to change decisionsWarnings often exist before disasters. Learn why ice reports, foam strikes and cold-weather concerns failed to change decisions, and how to test reach.
- When nature runs the experiment: natural tests of causeWeather, seasons and epidemics sometimes change conditions for us. Learn to read such events as tests, and to see what they cannot prove on their own.