HKB
a fair rate of interest over the whole industry? To enable us to think closely let us suppose for a moment that we can measure accurately what the chances are.
Suppose, then, that there were a precisely equal chance of success on the one hand and failure on the other in any enterprise, failure involving a complete loss of all the capital invested. Suppose, further, 6 per cent to be at the time a fair return on a perfectly secure investment. What would be the return which must be expected from the risky enterprise, in the event of its succeeding, before it will be undertaken? The reader may be tempted to answer, 12 per cent. But 12 per cent would not suffice. An equal chance of 12 per cent or nothing, as compared with a certainty of 6 per cent, does not mean that the risk in the former case is paid for to the tune of 6 per cent. It means that it is not paid for at all. In each case what a mathematician would call the expectation is a return of 6 per cent. The odds are evenly balanced; in the long run, over a large number of cases, if the law of averages works as we assume it does, you would get just as much from the one type of investment as the other. Now, risky enterprises will not, as a rule, be undertaken on terms like these; investors and business men will not take risks with the odds precisely equal; they must have them, or believe that they have them, in their favor.