One pound of government spending can put more than a pound into the economy

John Maynard Keynes argued that money spent by government doesn't stop with its first recipient: a paid construction worker spends part of their wage at a shop, whose owner spends part of that too, and so on. This 'multiplier effect' means a stimulus can grow the economy by more than its original cost, especially when demand is weak.

— John Maynard Keynes, The General Theory of Employment, Interest and Money — 1936
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