In MES Rothbard continually argues that the rate of interest is set by time preference alone and not by the productivity of loans. This seems to me to be absolute nonsense. In chapter 6 section 7 Rothbard provided a critique of the neoclassical theory of the setting of the interest rate. In this he didn’t seem to really give a compelling reason as to why the productivity and demand for loans doesn’t play a part in the setting of the interest rate.
So here’s a praxeological attempt to explain why the interest rate would be set both by time preference and the productivity of loans.
Assumptions: Uniformity of the interest rate through competition, perfect certainty as to the yield of the loan, no increase in prices.
No individual will loan out money at a rate lower than their time preference, their valuation of current goods over future goods, so a borrower must offer at least enough money to satisfy the lender’s time preference. If a borrower is investing in capital goods and he knows that this investment will result in an increase in his profit margin of X, then he will be willing to pay at least X-.01 percent on the interest rate, but he can still pay a total of X on interest. Let’s indeed say that he is willing to pay the entirety of X for the loan because this will put his firm in a more advantageous state, however he will not pay more than X because then he believes that the loan is not justified.
Now let’s take a similar analysis of anticipated profit margins and apply them to other firms, but let’s say that the aggregate expected loan pay off is Y and all businesses are willing to pay an interest rate of Y in order to obtain their loan.
Fortuitously for the borrowers the time preferences of many are far lower than Y, and they are therefore willing to compete for loans. However, unless all of the time preference at the absolute minimum amount of money, offered that is to say Z, covers the loan, then the rate of interest will be bid up by the productivity of investment. If investment productivity did not matter then they would not be bid up any further than the minimum rate that ANY individual was willing to lend on the market. This is due to the fact that individuals will not invest at a loss. If no individual was willing to lend below a rate of 5 percent per year but no business was expecting to receive a profit of more than 2 percent, then no company would borrow funds or invest.
For one to maintain that expected profit margins from investment do not effect the rate of interest then this indeed does not take into account the fact that entrepreneurs will, all else equal, avoid running at a loss, and that if there is scarcity of a good, then individuals will bid up the price so long as the transaction is still mutually advantageous, so if there is a scarcity of loans at one rate, then it will be bid up by the purchasers of loans by offering a higher rate, bringing more investors into the market.
Please tell me what is wrong with my analysis, although I could have been more clear and concise I hope that I showed that all else equal borrowers will bid up the price depending on what they are willing to borrow at, and that depends upon what transaction is still advantageous, which in turn depends upon the expected contribution of the loan to a final product. This is praxeological.
I feel as though I must be misunderstanding Rothbard here, thoughts?