issue of this Journal, Bierman 2 and Hass (BH) construct a steam roller for the purpose of cracking a nut.BH's paper is essentially an attempt to use subjective probabilities to set yields on new bond issues.I am concerned primarily with the first two-thirds of their paper (pp.757-67), which, in my view, contains a number of statements that are seriously misleading.The first section of this comment will briefly summarize those portions of pp.757-67 of their paper.The second section contains the comment itself, plus a few observations on the final portion of their paper. I.(1) Assuming a risk-neutral buyer of debt issues and given what they call the "probability of survival" (P), BH show how to obtain the "required" yield on a new risky perpetuity (their equation 4, p. 759).They use a perpetuity in order to avoid, at the outset, the complications created by the fact that (risky) borrowers must also, in every case, make not only interest payments but also payments on principal.They then state as their conclusions to this initial section of their paper that: Deceased, formerly University of North Carolina, Chapel Hill.The