Once upon a time, printing money was another euphemism for inflation, but in this day of Orwellian Newspeak, it is called "Quantitative Easing" or something else. (Krugman holds that inflation is measured only by indexes, so just creating more money in and of itself is meaningless.) Furthermore, according to Krugman, real-live evidence of inflation is, well, irrelevant whenever Krugman says so. He recently wrote:
For two years we’ve been warned that inflation, even hyperinflation, was just around the corner; instead, disinflation has continued, with core inflation — which excludes volatile food and energy prices — now at a half-century low. (Emphasis mine)In other words, two situations in which you really will be feeling the brunt of higher prices is nothing more than volatility at work. However, does anyone really think that food prices will be volatile downward anytime soon?
This is part of the "heads I win, tails you lose" arguing style that Krugman employs. Housing prices have been depressed for a long time, but they were way out of kilter and even Krugman will admit that, and that has had an effect upon the price indexes.
What Krugman does not say, however, is that food, energy, and commodities in general are quite sensitive to changes in the value of money and often act as the proverbial canary in the coal mine. Because Krugman hates gold and silver (or any other kind of "hard" money) and commodities in general, anything that might reflect the fact that people are escaping the dollar and buying something that can hold its value relative to money is something that is evil.
(Of course, anyone who disagrees with Krugman on this subject is a "zombie" and not even worthy of being permitted to inhabit the same planet as Krugman.)
So, inflation is the key in Krugman's view. Save the world by flooding it with dollars or whatever, but flood the world.