Today's Banks are by necessity a sort of Ponzi Scheme

Martin Wolf's suggestions for banking reform may all be admirable but they are basically just reshuffling the chairs on the deck of the Titanic. Banking as we know it is to some extent by necessity a ponzi scheme, to accept that longer-term loans are financed with deposits on shorter notice periods is a concept that may work in the days when investors were very loyal (or lazy). A much better solution would be limited purpose banking (as promoted by Laurence Kotlikoff) where banks become some sort of mutual fund.