In my 1981 paper ‘The flock and the sheep’ (J.I.A., 108,361) I explained that I had been writing a number of historical essays and that the paper was based on those which were about distribution of surplus. Some of the remaining essays fall naturally into a set under the general heading of valuation and it is these which have been combined into the present essay. It also includes something which has been on my conscience for a number of years—a critical examination in the light of history of my 1952 paper on the principles of valuation (J.I.A., 78, 286).