On the whole, then, we may take it that the principle of the supertax is based on the conception that when we come to an income of some £5,000 a year we approach the limit of the industrial value of the individual.12 We are not likely to discourage any service of genuine social value by a rapidly increasing surtax on incomes above that amount. It is more likely that we shall quench the antisocial ardour for unmeasured wealth, for social power, and the vanity of display.
These illustrations may suffice to give some concreteness to the conception of economic justice as the maintenance of social function. They serve also to show that the true resources of the State are larger and more varied than is generally supposed. The true function of taxation is to secure to society the element in wealth that is of social origin, or, more broadly, all that does not owe its origin to the efforts of living individuals. When taxation, based on these principles, is utilized to secure healthy conditions of existence to the mass of the people it is clear that this is no case of robbing Peter to pay Paul. Peter is not robbed. Apart from the tax it is he who would be robbing the State. A tax which enables the State to secure a certain share of social value is not something deducted from that which the taxpayer has an unlimited right to call his own, but rather a repayment of something which was all along due to society.
But why should the proceeds of the tax go to the poor in particular? Granting that Peter is not robbed, why should Paul be paid? Why should not the proceeds be expended on something of common concern to Peter and Paul alike, for Peter is equally a member of the community? Undoubtedly the only just method of dealing with the common funds is to expend them in objects which subserve the common good, and there are many directions in which public expenditure does in fact benefit all classes alike. This, it is worth noting, is true even of some important branches of expenditure which in their direct aim concern the poorer classes. Consider, for example, the value of public sanitation, not merely to the poorer regions which would suffer first if it were withheld, but to the richer as well who, seclude themselves as they may, cannot escape infection. In the old days judge and jury, as well as prisoners, would die of gaol fever. Consider, again, the economic value of education, not only to the worker, but to the employer whom he will serve. But when all this is allowed for it must be admitted that we have throughout contemplated a considerable measure of public expenditure in the elimination of poverty. The prime justification of this expenditure is that the prevention of suffering from the actual lack of adequate physical comforts is an essential element in the common good, an object in which all are bound to concern themselves, which all have the right to demand and the duty to fulfil. Any common life based on the avoidable suffering even of one of those who partake in it is a life not of harmony, but of discord.
But we can go further. We said at the outset that the function of society was to secure to all normal adult members the means of earning by useful work the material necessaries of a healthy and efficient life. We can see now that this is one case and, properly understood, the largest and most far reaching case falling under the general principle of economic justice. This principle lays down that every social function must receive the reward that is sufficient to stimulate and maintain it through the life of the individual. Now, how much this reward may be in any case it is probably impossible to determine otherwise than by specific experiment. But if