The idea that the hard goods are sold for "imaginary numbers" is popular but a bit of a misnomer.
These "imaginary numbers" are actually claims on future income generated by the United States economy. It is true that they are "imaginary", in the sense that any property ownership is imaginary in a way that a toaster is not. The most common form is Treasuries, which the government then pays interest on and which must eventually be either repaid or rolled over.
So it would be more correct to say that China is trading hard work building goods in exchange for claims on future US income.
These "imaginary numbers" are actually claims on future income generated by the United States economy. It is true that they are "imaginary", in the sense that any property ownership is imaginary in a way that a toaster is not. The most common form is Treasuries, which the government then pays interest on and which must eventually be either repaid or rolled over.
So it would be more correct to say that China is trading hard work building goods in exchange for claims on future US income.