Final answer:
John Maynard Keynes advocated policies that would increase aggregate demand to decrease unemployment caused by recessions through expansionary fiscal policies such as tax cuts or increases in government spending.
Step-by-step explanation:
John Maynard Keynes advocated policies that would increase aggregate demand as a way to decrease unemployment caused by recessions. Keynesian macroeconomics argues that during recessions, the government should implement expansionary fiscal policies to stimulate consumption and investment. This can be done through tax cuts or increases in government spending, which would shift the aggregate demand curve to the right. By doing so, the economy can reach full employment and decrease unemployment.