Please show me a donut shop that does barter
Obviously I can't, but that was not your original point. You claimed the Mona Lisa couldnt be exchanged for a donut.
I was just pointing out that as absurd and unlikely for it to ever happen, that yes, it could be exchanged for a donut.
I have no quarrels over the Mona Lisa being a very poor, inefficient, inadequate medium of exchange for the transfer of money.
But money it is.
And my initial point above is, before humans developed the convenience of currency, money obviously existed. The creation of currency in coins and notes allowed us to abandon the inefficiencies of barter to such an extent that we apply the notion of 'money' to currency and can comfortably classify the Mona Lisa as a tangible asset, rather than tangible asset and (extremely inefficient medium of exchange).
So convenient is the currency system as means to exchange money that we have tended to consider money as currency of notes and coins and digital entries on a ledger.
My view is however that money is everything and everywhere that humans relate to and apply value to.