And if you want to predict the future, the most accurate source of information is the past.

Copying this in from our most recent Pandemic Megathread:

From our perspective as historians, we feel it is important to stress that we can learn history, but we cannot learn simple lessons from it. Sure, history can teach some things by example that science can teach by experiment, like the merits of quarantine. But when we look at the big picture stuff, that notion goes out the window.

Fundamental to the modern study of history is the concept of difference, which the 19th century German historian Leopold Ranke famously expressed with the words "every age is immediate to God." What that means is that every historical event, process, society and system must be understood on its own terms. Everything has a unique context and must develop in ways that are specific to that context. The American, French and Russian Revolutions are all political revolutions, but their causes, course and consequences are completely different; how would we determine on the basis of these examples "what happens in a revolution"? As Max Weber argued, when we generalise about historical phenomena like "feudalism" or "family" or "revolution" or "pandemic" we are not observing the universal laws of history at work but creating patterns out of random facts by applying the conceptual frameworks we are interested in. This effort to make sense of things is important, but it has limits. If we are too eager to make many things into examples of one Thing, we're likely to gloss over crucial differences. If we look too hard for similar causes and outcomes we will be up to our necks in confirmation bias, ignoring what the sources are really telling us.

What this means in practice is that historians usually don't presume to know what the next X will look like based on past examples of X. Too much depends on a context that has never been seen before. At the same time, too much of what we know about past cases depends on factors that were only relevant in those cases and do not apply in the here and now. Trying to separate the generally applicable from the unique and contingent is often simply not possible. Unfortunately, the extent to which the Plague of Athens, the Black Death and the Spanish Flu can teach us about the development and long-term effects of a pandemic in the modern world is extremely limited.

That said, people in the ancient world or the early modern world are still recognisably people, and we can recognise parts of ourselves in them. While we can't easily extrapolate from historical events to the present, it can be useful to look at the past as a guide to what about a current situation is uniquely 2020 and what is shared with other events. History is the story of us. We experience time as a progression of events; we come to perceive that there was a time before us. That people lived before us, some of whom we know, others that are strange. Our world is built on the things that they have said and done, and their story is our story. It is a story we want to know. Not necessarily for any particular practical purpose, although there can be practical applications of historical research and analysis, but because we want to know more about ourselves, how we and our world became as we are.