Reading Paul Krugman calls to mind that I never reacted to John Cochrane's July 2012 failure to mark his beliefs to market and, instead, doubling down on his claim that the biggest risk the U.S. economy faces is that of becoming "Argentina" "quickly".
I must say that if I had been opining stridently about issues of public policy without doing my homework five years ago, and if between then and now events had developed in directions strongly contrary to my expectations, I would not double down on what I had thought then--I would rather try hard to do my homework and to mark my beliefs to market.
And if I were going to criticize people for not citing my work, I would not claim that a sentence they wrote which comes immediately after a four-paragraph quote from me as an example, and I would have read their explanation of why they think expansionary fiscal policy right now does not raise the risks of "fiscal dominance" rather than remain in ignorance of it.
But to each his own.
Cochrane:
The Grumpy Economist: Krugman, Delong and Inflation: Yes, I've been worried for some time that our current debt could lead to inflation. And yes, that inflation has so far not happened…. Well, they made fun of Friedman when he said in 1968 that inflation was coming. They made fun of Greenspan when he said in 1996 that stocks seemed awfully high, and stocks went up for a few more years.
I gotta interrupt: Friedman in the late 1960s was right. He--correctly--saw inflation rising because he had theory and evidence on supply and demand in the labor market. But Greenspan in 1996 was wrong: since late 1996 the S&P 500 has produced a real return of 5.6%/year.

Does Cochrane know this?
Has he looked at the numbers?
Back in 1996 I agreed with Greenspan. I worried too that the market was overvalued. We thought this for a bunch of reasons. We were wrong.
Why does the fact that our worries were wrong then make Cochrane's worries right now?