The second conceivable rule is that of proportional needs. It would require each person to be rewarded in accordance with his capacity to use goods reasonably. If the task of distribution were entirely independent of the process of production, this rule would be ideal; for it would treat men as equal in those respects in which they are equal; namely, as beings endowed with the dignity and the potencies of personality; and it would treat them as unequal in those respects in which they are unequal; that is, in their desires and capacities. But the relation between distribution and production cannot be left out of account. The product is distributed primarily among the agents of production only, and it must be so distributed as to give due consideration to the moral claims of the producer as such. The latter has to be considered not merely as a person possessing needs, but as a person who has contributed something to the making of the product. Whence arise the questions of relative efforts and sacrifices, and relative productivity. Since only those who have contributed to the product participate in the distribution thereof, it would seem that they should be rewarded in proportion to the efforts and sacrifices that they exert and undergo. As an example of varying effort, let us take two men of equal needs who perform the same labour in such a way that the first expends 90 per cent. of his energy, while the second expends 60 per cent. As an example of varying sacrifice, let us take the ditch digger, and the driver who sits all day on the dump wagon. In both these examples the first man expends more painful exertion than the second. This would seem to make a difference in their moral desert. Justice would seem to require that in each case compensation should be proportionate to exertion rather than to needs. At any rate, the claims of needs should be modified to some extent in favour of the claims of exertion. It is upon the principle of efforts and sacrifices that we expect our eternal rewards to be based by the infinitely just Rewarder. The principle of needs is likewise in conflict with the principle of comparative productivity. Men generally demand rewards in proportion to their products. The validity of this demand we shall examine in a subsequent paragraph. Like the rule of arithmetical equality, the rule of proportional needs is not only incomplete ethically but impossible socially. Men's needs vary so widely and so imperceptibly that no human authority could use them as the basis of even an approximately accurate distribution. Moreover, any attempt to distribute rewards on this basis alone would be injurious to social welfare. It would lead to a great diminution in the productivity of the more honest, the more energetic, and the more efficient among the agents of production. _The Canon of Efforts and Sacrifice_