F.— ECONOMIC SCIENCE AND STATISTICS 149 



of the claims of different individuals with one another. The preferences 

 notified in the model market are of the form that a given individual 

 prefers an nth unit of X to an 7;/th of Y. The need of one individual is 

 not compared with that of another. 



Yet one is tempted to make such comparisons. For example, Marshall 

 says in the Pmiciples that the marginal utility of twopence is greater in 

 the case of a poorer man than in that of a richer. If such comparisons are 

 allowed, recommendations for a more even distribution of income seem 

 to follow logically. They give scope for a wide range of recommenda- 

 tions not sponsored by our original criterion. 



Objection to this enlargement of the field of prescription may be based 

 on two grounds. 



(i) It may be urged that the economist hereby goes outside his proper 

 ' scientific ' field. This point is strongly urged by Prof. Robbins. 

 Whether the wth unit of X has greater or less utility than the mth. of Y 

 to a given individual may be made the subject of test. He can be given 

 the choice. But there are no ' scientific ' means of deciding whether the 

 72th of X has greater or less utility to individual P than the wrth of Y has 

 to another individual Q. The choice can never be put. This implies 

 that we cannot decide whether two pence have more utility to a mil- 

 lionaire or a beggar. Yet we may have a shrewd suspicion. But this, 

 we are told, is ' unscientific,' for lack of a test. This objection would be 

 very weighty if economics itself were a mature and exact science. Yet 

 in fact its achievements outside a limited field are so beset on every side 

 by matters which only admit of conjecture that it is possibly rather 

 ridiculous for an economist to take such a high line. 7Te7T;ai.8£U[j,evou yap 

 eaxiv ettI tocoutov to dcxptPe? etul^yjtsiv >ca6' exacrxov y£VO(;, ecp' ocrov y) tou 

 TTpayixaxo? cpuoi? i-K\Zzjz-a.u^ Can we afi"ord to reject this very clear 

 finfiing of common sense ? Of course great caution must be exercised 

 in not pushing the matter too far. Since the evidence is vague, we must 

 not go further than a very clear mandate from common sense allows. 



It is not altogether certain that the gulf between the prescriptions of the 

 classical economists and those of, shall I call them, the welfare school 

 is as great as Prof. Robbins implies. There is no doubt that the marginal 

 utility of twopence to a given man at a given time and in given other 

 circumstances is less if he has ^^ 1,000,000 a year than if he has ^zs, a year, 

 since he will spend the £2:^ on things which he prefers per id. of cost to 

 the things on which he would spend the remaining ^999,975. The further 

 postulate that the twopence has lower utility to a millionaire than to a 

 £2^ per annum man is based on some sort of assumption about the equality 

 of men in regard to their needs, which must not be pressed too far. But 

 so also do the prescriptions favourable to free markets. For the indi- 

 viduals who gain by the opening of a market are often difi'erent from those 

 who suflFer some loss. Consider the Repeal of the Corn Laws. This 

 tended to reduce the value of a specific factor of production, land. It can 

 no doubt be shown that the gain to the community as a whole exceeded 



* Aristotle, Ethica Nicomachea, 1094b. ' For an educated person should 

 expect to obtain precision in each branch of study to the extent which its nature 

 permits.' 



