Not much. Early economies relied on mutual trade. I give you X and in return you give me Y. Soon we realized that you cannot always give Y in return immediately, so we invented accounting to keep track of your promise to give me Y at some point in the future. As time went by eventually we stopped caring about getting Y back in return and started taking an interest in collecting the promises themselves (i.e. profit).
Why would someone want to collect promises? That seems rather silly, right? What having a lot of promises gives you is social standing. People treat you differently — better — when they give you their promises. If traditional labor goes away, the economy simply becomes you promising to hold those who have things in the highest regard; to be there as their friend when they call for you to. That is the same modern economy we already have but with less steps.
Why would someone want to collect promises? That seems rather silly, right? What having a lot of promises gives you is social standing. People treat you differently — better — when they give you their promises. If traditional labor goes away, the economy simply becomes you promising to hold those who have things in the highest regard; to be there as their friend when they call for you to. That is the same modern economy we already have but with less steps.