In the 19 forties, pull samuelson drew a diagram of the whole economy that made it accessible for enginers to understand. He drew it as a set of pipes, like plummbed pipes, going round and round in a circle,. And it was the idea that money flows around between businesses and households. It's actually deeply embedded in the thermo dymathe thermo dynamics of the planet daily drawing in energy and matter, white. So as ecological economists say, like home and daily, the economy is actually a thermo dynamic system. Think of it as an hour glass, resources and energy flowing one way throug it to a completely different starting point.