The economic equivalent of “famous for being famous” is the idea of a rise in confidence because of a policy whose main transmission channel is confidence. The discussion about quantitative easing is precisely this. It is as self-referential as the statement that it works because it works.
An example of such circularity was the forecast by the European Central Bank this month, which predicts a solid economic recovery in 2016 and 2017 on the grounds that QE would work.
The forecast even suggested that inflation would rise close to the central bank’s target of just under 2 per cent within the next two years. Since the declared rationale for the ECB’s purchase of sovereign bonds was to raise inflation expectations, one might conclude that the programme was already working. What makes this even more amazing is that the ECB had not bought a single bond at the time. The only thing that changed is that everybody was suddenly more confident — because everybody else was.