I suspect there might be three types of knowledge
- Things everyone knows. Rather self explanatory: The United States won the Cold War, Beyonce is married to Jay Z, vaccines prevent disease.
- Things widely known to a small group. Specialist knowledge or domain expertise. I assume there are facts about concrete known to all Engineers, like how most economists know the Philips Curve.
- Things almost no one knows. What I had for breakfast, quantum mechanics, and answers to Peter Thiel’s interview question: “What important truth do very few people agree with you on“
I suppose we could add a fourth: things no one knows. Donald Rumsfeld’s unknown unknowns go here.
The GFC is usually compared to the Great Depression of the 1930s or Stagflation of the 1970s, but in what is a great candidate for #2, I recently discovered another Great Depression.
The First World War was the Great War until a bigger one came along. It turns out the Great Depression also usurped the title from one that came before, now known, rather unimaginatively, as the Long Depression. It lasted from 1873 to 1896 (although in some places it ended much earlier).
To give a sense of perspective, imagine a depression starting in 2008 lasting until 2031. We would be just about halfway.