If Swiss voters support the referendum, fractional reserve banking will need to stop. Under this model, banks retain only a small fraction—typically a tenth—of deposits and lend the rest. MoMo wants a 1:1 ratio; hence MoMo's title for the initiative: Full Money.
The initiative has a long history in economics going back to the 30's in the US where economists—most prominently, Irving Fisher—developed the Chicago Plan. Read more on this in a very informative article by Jason Voss at the CFA Institute.
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