out of it as B, who derives the same annual sum from heritable property; A having usually a demand on his income which [pg 545] B has not, namely, to provide by saving for children or others; to which, in the case of salaries or professional gains, must generally be added a provision for his own later years; while B may expend his whole income without injury to his old age, and still have it all to bestow on others after his death. If A, in order to meet these exigencies, must lay by £300 of his income, to take £100 from him as income-tax is to take £100 from £700, since it must be retrenched from that part only of his means which he can afford to spend on his own consumption. Were he to throw it ratably on what he spends and on what he saves, abating £70 from his consumption and £30 from his annual saving, then indeed his immediate sacrifice would be proportionally the same as B's; but then his children or his old age would be worse provided for in consequence of the tax. The capital sum which would be accumulated for them would be one tenth less, and on the reduced income afforded by this reduced capital they would be a second time charged with income-tax; while B's heirs would only be charged once.
The principle, therefore, of equality of taxation, interpreted in its only just sense, equality of sacrifice, requires that a person who has no means of providing for old age, or for those in whom he is interested, except by saving from income, should have the tax remitted on all that part of his income which is really and bona fide applied to that purpose.
If, indeed, reliance could be placed on the conscience of the contributors, or sufficient security taken for the correctness of their statements by collateral precautions, the proper mode of assessing an