Milton Friedman discussed the possibility of setting the marginal social cost of printing one more unit of money to zero, implying that the real interest rate should be equal to the rate of deflation in the economy, but not everyone agreed with this. What reasoning did Phelps (1973) provide to argue against Friedman's rule? Which interpretation would be correct in the RBC model? Why?

Answer and Explanation:

Phelps criticized Friedman's position, because he said it was totally irrelevant to analyze the tax functions of inflation without assessing product demand, as Friedman suggested in his theory. He stated that this would only be possible if there was a way to predict an optimal rate of inflation in different situations of demand and supply, otherwise, in Phelps' words it would be the same as "Professor Friedman gave us Hamlet without a prince".

Phelps' positioning would be better considered by the RBC model, since this model is based on real and not imaginary facts.