@Alwyn Lewis "But I find it damn confusing to call a negative asset a liability; even if the arithmetic is correct, the logical meaning isn't.". Yes. Old language is not mapping cleaning onto a new structure.

@Jon Underwood @Alwyn Lewis === from above That means T-bonds are 'demand-assets' and not like commercial bonds which are 'term-assets' of no current value until they mature - since the money that bought them is in other hands.” --- me I think it's more accurate to say T-bonds are time-assets with a very liquid secondary market into which they can be sold. === from above “T-bonds in the UK) do not have to be repaid out of tax when they mature. “ No, the Tressury can do a Liability Swap to extend the maturity, just kicking the can down the road by issuing new bonds as payment for old bonds. --- me I think it's more accurate to say that T-bonds do have to be paid out (if that's the right phrase) at maturity, but doing so is just like any other treasury expense that can be financed by selling T-bonds, or doing a bond swap. Effectively, as bonds mature, they can be, and often are, paid off with new bonds.