Final answer:
In the early 1960s, economists believed the business cycle was solved. This era of confidence in controlling the business cycle with Keynesian principles is seen as incomplete by today's economic understanding.
Step-by-step explanation:
In the early 1960s, many leading economists believed that the problem of the business cycle, and the swings between cyclical unemployment and inflation, were a thing of the past. On the cover of its December 31, 1965, issue, Time magazine, then the premier news magazine in the United States, ran a picture of John Maynard Keynes, and the story inside identified Keynesian theories as 'the prime influence on the world's economies.' The article reported that policymakers have 'used Keynesian principles not only to avoid the violent [business] cycles of prewar days but to produce phenomenal economic growth and to achieve remarkably stable prices.'