Anything IS-LM can do, Fisher did better
Here’s what economists knew before the General Theory:
1. Monetary policy and velocity determine NGDP growth.
2. Velocity is positively related to interest rates (and hence investment booms and deficit spending may raise velocity.)
3. Wages and prices are sticky in the short run.
4. Because of point 3 a monetary shock may produce a liquidity effect for short term rates.
5. Because of point 3, money and velocity shocks can destabilize output in the short run.