このところエコノブロゴスフィアで貨幣はバブルか否かという論争が続いていたが、JP Koningというブロガーが、その議論のあらましをまとめると同時に、本ブログの10/20エントリで紹介した中央銀行国債消却を巡るGavyn Daviesの議論とその話とを結び付けている

The point of all this is that central bank assets are important. They are the key for understanding why modern central bank money is different from pure fiat money, why central bank money's future value > 0, and why financial assets (like corporate bonds) that pay out central bank money are not fundamentally worthless.
One reason to make a central bank independent is to cordon off a fixed set of assets that can be used to provide a permanent basis for the fundamental value of central bank money. In this respect, a central bank is like a special purpose vehicle. SPVs are subsidiaries to which a parent company has transferred specific assets. The vehicle has been structured to prevent the parent from tampering with the assets after the fact. The SPV issues its own liabilities to other investors using these ring-fenced assets as backing. A central bank, much like an SPV, has been hived off from its parent, the government, and as a result the holders of its liabilities, the public, can be sure that they have claim to a secure set of assets. If an SPV suddenly had its assets removed by its parent with no guarantee of replacement, the liabilities issued by that SPV would suffer. Same with the liabilities of a central bank.

Gavyn worries that the destruction of central bank assets would unleash inflation. He also points out that there are people who are worried about deflation, and they would welcome a destruction of central bank assets. Whichever way you stand, the point here is that central bank money has a fundamental value. The proof of this would be what Gavyn describes: a scenario in which the value of central bank money declines as central bank assets are destroyed.

ちなみにKoningが追記でリンクしたBritmouseのブログエントリでは、上記の「中央銀行の資産の毀損を歓迎する」立場からGavyn Daviesの議論を捉えている:

The argument Davies is making here is a familiar one about the effectiveness of a permanent versus temporary expansion of the monetary base. It is thus based entirely around expectations; that destroying a portion of the Bank’s assets boosts nominal GDP exactly because it is a way to signal that (some of) the monetary base expansion will be permanent, and will not (can not) be soon reversed by selling those assets again.

ここでBritmouseは、10/25エントリで紹介したToby Nangleやマービン・キングの懸念した点を、むしろ前向きの材料として捉えているわけだ。しかし同時に、その有効性について次のような疑念も示している。

I’m not sure that policy tool would be particularly useful; it is possible for the Bank to contract the monetary base by issuing bills or similar non-monetary liabilities. So I cannot see that the inflation target would automatically lose credibility as a nominal anchor.


What is necessary to avoid another crash is to simply point the nose in the right direction: abandon the inflation target and tell us you want faster nominal GDP growth. Set expectations around a clear nominal target, a level target, and print enough money to get expectations pointing the right way.

Britmouseはまた、JP Koningのエントリのコメント欄で、イングランド銀行国債の消却による名目GDP押し上げ効果を弱めるもう一つの要因として、財務省QEポートフォリオの損失に対し補償を約束した点を挙げている。

一方、市場マネタリストのカナダ代表であるNick Roweは、JP Koningのエントリのコメント欄や自ブログエントリで、資産が重要、という見方に疑義を呈している。それは、3年前の本ブログのこのエントリで紹介したシニョリッジの現在価値やこのエントリで紹介した中央銀行の資産の意義についての彼の持説の延長線上にあると言える(サムナーもRoweの議論に賛意を表している)。