Dear Dr's Summers, Krugman, Rogoff, et al. Please give a quick glance at "How Much Does Finance Matter", from the book, Keynes on the Wireless.
With all due respect, your version of Keynes does not match his own words. Read them.
Out of courtesy to Palgrave and Donald Moggridge, the editor, I will paste no more. Please get the publication and read it with your own eyes, in JMK's own words.
Truth in advertising...it's a thing.