Bringing to the table diverse perspectives is a pragmatic way of confronting such deep sources of uncertainty and deciding how to deal with them.
Secular stagnation: During World War II in the United States, many economists feared that at the end of the war, the economy would return to high pre-war levels of unemployment – because with the end of the war, demobilization, and the massive reduction that would take place in the defense budget, there would not be enough demand to maintain full employment.