"Conceptual framework" by Alan Blinder:
At any given moment, there is a core inflation rate toward which the actual inflation rate tends to gravitate. This rate is determined by fundamental economic forces, basically as the difference between the growth rates of aggregate demand and aggregate supply.
Conclusions by Scott Sumner:
I hope that we can both agree that slow growth in AS did not cause the high inflation of the 1970s. Yes ... inflation was completely demand-side.