Why some inflation can be good for you

Paul Krugman writes in Not Enough Inflation:

Fundamentally, the right wants the Fed to obsess over inflation, when the truth is that we’d be better off if the Fed paid less attention to inflation and more attention to unemployment. Indeed, a bit more inflation would be a good thing, not a bad thing. 

He goes on to write:

And, beyond that, would a rise in inflation to 3 percent or even 4 percent be a terrible thing? On the contrary, it would almost surely help the economy.

How so? For one thing, large parts of the private sector continue to be crippled by the overhang of debt accumulated during the bubble years; this debt burden is arguably the main thing holding private spending back and perpetuating the slump. Modest inflation would, however, reduce that overhang — by eroding the real value of that debt — and help promote the private-sector recovery we need. Meanwhile, other parts of the private sector (like much of corporate America) are sitting on large hoards of cash; the prospect of moderate inflation would make letting the cash just sit there less attractive, acting as a spur to investment — again, helping to promote overall recovery.