Wie kann also ein Forderung auf Geld selbst Geld sein? Das ist
verwirrend.

"The debate about whether the bank deposit is a particular form of money or only a promise to pay money is a debate that cannot be resolved definitively because the answer depends on the problem at hand. To a household, a deposit is payment. To a bank, a deposit is a promise to pay reserves, since net clearing must be settled in cash."

"Much of the ink spilled on the vexed question of whether money is exogenous or endogenous could have been saved by greater clarity about the level of analysis.

Everyone accepts that credit is endogenous, so the question of whether money is endogenous depends on whether the assets covered under the operative definition of money are more nearly promises to pay, or means of payment. The fact that what appears as credit and money depends on one’s point of view implies that what appears as endogenous and exogenous is equally context specific. Taking the entire hierarchy of money as the object of analysis, rather than just money or just credit, allows one to place the insights of competing schools in their proper context. Not currency school or banking school, but both, each in its proper place."

http://economics.barnard.edu/sites/default/files/inline/what_is_monetary_economics_abou...