In the second, the subject being learned is a social construct, a consequence of the learning activity and decisions based on learned knowledge. Everyone learns certain recognizable pieces of paper have value and is willing to accept the paper in return for the provision of goods and services. But these pieces of paper have value only because everyone is willing to accept them. A hyperinflation is the unwinding of this common understanding. Another example is financial asset prices.
Investors try to discern patterns in financial asset prices to predict profit opportunities.
But the trading decisions they make, based on the information they collect, determine the price patterns they are trying to learn. For more than a century, sociologists have referred to facts, such as the use of paper money and the pattern of stock prices, as social facts. Economists have long been cognizant of the nature of social facts. The hypothesis that stock market prices follow a random walk is based on the argument that, if there were a persistent pattern, traders would trade against it until it disappeared. But this view is overly simplistic.