That book by this man inspired the IS-LM model and rejected the idea that that supply creates its own demand and argued that an economy with full (*) employment was really an special case.
One of this man's books claims that long-run expectations could not be quantified and were driven more by "animal spirits"than rational weighing of risks.  One mathematical model based on this man's most influential book explains shifts in aggregate demand and was developed by Hicks and Hansen. That book by this man inspired the IS-LM model and rejected the idea that that supply creates its own demand and argued that an economy with full (*) employment was really an special case. This man attacked the Treaty of Versailles in The Economic Consequences of the Peace and argued for government spending to boost demand during depressions. For 10 points, name this British father of modern macroeconomics who wrote The General Theory of Employment, Interest, and Money. 
One of this man's books claims that long-run expectations could not be quantified and were driven more by "animal spirits"than rational weighing of risks.  
John Maynard Keynes