Larry Summers (1983):
The first way to find a topic is to open Keynes's General Theory at random, read what's on that page, and math it up…
John Maynard Keynes (1936):
The General Theory of Employment, Interest and Money: Clearly we do not mean by ‘involuntary’ unemployment the mere existence of an unexhausted capacity to work. An eight-hour day does not constitute unemployment because it is not beyond human capacity to work ten hours. Nor should we regard as ‘involuntary’ unemployment the withdrawal of their labour by a body of workers because they do not choose to work for less than a certain real reward. Furthermore, it will be convenient to exclude ‘frictional’ unemployment from our definition of ‘involuntary’ unemployment. My definition is, therefore, as follows: Men are involuntarily unemployed if, in the event of a small rise in the price of wage-goods relatively to the money-wage, both the aggregate supply of labour willing to work for the current money-wage and the aggregate demand for it at that wage would be greater than the existing volume of employment.
Robert Hall(2013): The Routes into and out of the Zero Lower Bound:
To the extent that high unemployment is an equilibrium, the stability of inflation in the presence of persistent high unemployment is less of a mystery. The tradition of regarding high unemployment as a disequilibrium that gradually rectifies itself by price-wage adjustment may rest on a misunderstanding of the mechanism of high unemployment….
Not, mind you, that I am complaining about the very-smart but never-conventional Hall: the paper worries about the right things, says a lot of things that are true, says a lot of things that might be true and that provoke insight, and says nothing that is known to be false.
But it is striking that useful and important frontier work in economics can still be done in 2013 by mathing-up pieces of the General Theory…