MR is marginal revenue, and MC is marginal cost. It means that over time the cost of producing additional units will become the same as the cost of producing the units, either because opening additional lines of production requires debt that has to be serviced or because competition drives down the price until there's no more delta. Both at sane time, really. The property part means that you get to keep the fruits of your labor unencumbered. If you don't, then you're someone else's MR=MC, their marginal unit. Over time, people selling their labor will keep less and less delta. That's why it results in genocide and should be on the sane page in the textbooks. I was a pain in the ass for my professors, and that's possibly why I've never found employment in economics. The incentive structure favors sycophants.