A fiat currency (such as the US Dollar)
is composed of debt—credit advanced based on a promise of future growth—
it is unclear how and with what the remaining oil will continue to be purchased.
The end of growth is an imponderable;
start talking about it
, and everyone suddenly decides that it's lunchtime and starts ordering drinks.
At least the French have a proper word for it: décroissance (literally, “de-growth”);
here in the anglophone world all we can do is gibber and mumble about “double-dips.”