John Maynard Keynes: The General Theory of Employment, Interest and Money.
That will probably do more to increase your understanding of economics than any other single book you could pick, Keynes being ridiculously.. better.. than the typical economist, and is in any case a highly recommended prelude to any further readings. - among other things because lying about what Keynes says has become a very popular sport, so familiarity with the original is very useful for detecting later horseshit.
When you take a book by Keynes down off the shelf, you're not taking Keynes himself down off the shelf. It's not like those heads in jars from Futurama. It's a book. Its core contents have been synthesised for a modern audience, with the benefit of decades of subsequent analysis, in every contemporary macroeconomics textbook worth its salt.
It might be worth your time, at some point, to read the original Keynes, just as it might be worth your time to read the original Origin of Species. But don't fool yourself into thinking you're tapping into the secret wi...
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