A great book that talks about what money really is -- is by David Graeber "Debt the first 5,000 Years". Graeber is an anthropologist as well as someone who knows about the economy. Did you know that the earliest written records we have are of ledgers? Money was virtual, then came credit, then came money (gold & silver) this was created by the state and people needed to acquire it in order to pay taxes. The state used this to pay for armies. Lastly, came barter and that shows up only when money collapses - so all of the stories we were told about barter are false. IT was not barter than money -- WRONG. It was money than barter. I recommend everyone read this book, gives great insight to debt and what it actually is.