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Saving does not equal investment


  • Boonserm Booncharoenpol

    (Faculty of Economics Krirk University)


SAVING DOES NOT EQUAL INVESTMENT John Maynard Keynes confused economists and politicians all over the world when he wrote, “Saving is necessary to equal investment” together with a few equations to confirm his idea and finally concluding that S = I. There have been repeated discussions about how saving can equal investment, accidentally or with certainty. We may think that Keynes explained about how saving money is used in the same amount either to invest by savers or by borrowers. But this is not what he meant. Keynes merely wrote that saving is residual. Residual from what? This paper shows that S always equals I in a closed economy. But even as S equals I, saving does not equal investment. Because I is investment but S is not saving.

Suggested Citation

  • Boonserm Booncharoenpol, 2005. "Saving does not equal investment," Macroeconomics 0510014, EconWPA.
  • Handle: RePEc:wpa:wuwpma:0510014 Note: Type of Document - doc; pages: 2

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    References listed on IDEAS

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    Cited by:

    1. Anton, Roman, 2015. "Monetary Development and Transmission in the Eurosystem," MPRA Paper 67323, University Library of Munich, Germany, revised 08 Oct 2015.

    More about this item


    Keynes; saving; investment; S does not equal I; Confusion about saving;

    JEL classification:

    • E - Macroeconomics and Monetary Economics

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