How have people tried to gain knowledge about the future (Zukunftswissen), and what do modern forecasts have in common with older methods?

From fortune-telling rituals to statistical forecasts, every method tries to read the future out of something available today. Modern projections mostly extend present trends, so they can only be as good as the assumption that the trend continues.

"The wish to know what the future looks like is as old as humanity itself" (Ute von Reibnitz, Szenario-Technik, 1991). The attempts range widely:

• Divination: tarot cards, oracles, or Zurich's Böögg, a snowman effigy burned at the Sechseläuten spring festival, where the time it takes for its head to explode is said to predict the summer.
• Forecasts and projections: a bank's interest-rate forecast for the next years, or an OECD baseline scenario for greenhouse-gas emissions up to 2050. These use data and models, and they are far more useful than a burning snowman.

But a projection is still built on the past: it assumes the conditions that produced today's trend stay in place. That is exactly what fails at turning points, the lesson of the turkey illusion. Forecasts are tools for the probable future, not knowledge of the future.

Go deeper:

• Wikipedia: Futures studies — how the systematic study of futures differs from prediction.
• Wikipedia: Sechseläuten — the Böögg and its "summer forecast".