john maynard keynes, 1st baron keynes, cb (5 june 1883 – 21 april 1946) was a british economist. his ideas, called keynesian economics, had a big impact on modern economic and political theory. his ideas also had a big impact on many governments' tax and economic policies. he said governments should use tax and banking measures to stop the effects of economic recessions, depressions and booms. he is one of the fathers of modern theoretical macroeconomics.