rs all positive cash flow until moment z, and cannot in itself be affected by later transfers in, q simplifies by (A1.6a) to rate of return. This was Boehm Bawerk’s insight, although he was not mathematical, in equating time preference rate to rate of return r. Thus (2.2) and (2.3) give dPV(x)dx=F, (zje"’ dz an

arned of Rae’s work, and dedicated later editions to him. Period of production theory thrives today in the Austrian School, which had been founded by Boehm Bawerk’s teacher Carl Menger in 1871. (Menger was the guy who squabbled with Schmoller in Chapter 2.) It has found little favor elsewhere. The period seemed