If you want to determine what people believe, don’t listen to what they say. Rather, closely watch what they actually do. In recent days, the stock market has been hovering near all-time record highs and business leaders have been assuring us that good days are ahead. But meanwhile many of our most famous billionaires have been doing things that indicate that they are extremely concerned about what is coming in the future. For example, during the first two months of this year Jeff Bezos, Jamie Dimon and Mark Zuckerberg “have all sold big chunks of shares in their own companies”…...