That’s a great poster — but:
1. Keynesian economists aren’t the only ones who use models — all quants do. In Keynes’ time nearly all economists used a few key indicators, and their particular economic theory to do analysis. The number of quants have increased with the increase in cheap computer power. Quants know little about any economic theory, or even economics (which is, fundamentally, a social science, regarding the behaviour of “economic man”), and plenty about making econometric models, with hundreds of variables.
2. Keynes was not a Keynesian, as we understand the term today. He specified a narrow set of circumstances (mainly involving a “liquidity trap”) that would justify government deficit spending. He also insisted that government debts should be repaid ASAP.
All that’s true, and so is the fact that limey poofter Keynes was wrong about everything.
If Kamarade Franklin Delano Rooseveltovich had gone with sane economists instead of the pickle-smoocher from Piccadilly, there need have been no Great Depression.