Greg Mankiw in the NYT on November 28, 2008:
IF you were going to turn to only one economist to understand the problems facing the economy, there is little doubt that the economist would be John Maynard Keynes. Although Keynes died more than a half-century ago, his diagnosis of recessions and depressions remains the foundation of modern macroeconomics. His insights go a long way toward explaining the challenges we now confront.
Contrast that with Greg Mankiw in the European Economic Record in 1992:
The General Theory is an obscure book … We are in a much better position than Keynes was to figure out how the economy works.