“In the long run we are all dead”: What did Keynes mean by that?

Aca

"In other words, the famous “in the long run we are all dead” statement was about the long run and short run effects as predicted by the quantity theory, not about deficit spending or Keynesian stimulus. In essence, Keynes’s passage boils down to the instability of the demand to hold money.

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So what we have here is Keynes the quasi-monetarist advocating short-term monetarist solutions to changes in the demand to hold money. To avoid destabilising price level shocks, Keynes argued that the bank rate must be changed. The neoclassical theory held that in the long run markets would adjust and return to full employment equilibrium in response to shocks, and Keynes seems to have agreed, but – like other Marshallian neoclassicals – argued that short term pain from the destabilising forces of deflation during recessions was unnecessary and monetary interventions should be used to stabilise economies."

Matias Vernengo

Paul Krugman, Brad DeLong (y otros)