Sec. 13. #Principles of administration.# Whatever forms of taxes are adopted, whether on property or income, whether at proportional or at progressive rates, their justice and expediency depend largely on their administration.  Principle and practice in this, as in most affairs, may go far apart.  The administration of taxation should be economical, certain, and uniform.  Some laws are more easily and economically executed than others.  The time of collection should be as convenient as possible for the citizen, and the mode of payment should be the most simple.  The utmost certainty is desirable as to the time, method of payment, and amount.  Taxation that, in its principle, is variable, shifting, or dependent on personal whim and favoritism, is despotism.  But the greatest evils, in practice, result from the failures in assessment.  The assessment of taxes has to be intrusted to men with fallible judgment, imperfect knowledge, and selfish interests.  The assessor is as near a despot as any agent of popular government to-day.  Not infrequently men of proved incapacity in every private business they have attempted are, for partizan or corrupt reasons, selected as assessors, and are given the power of passing judgment on the value of millions of dollars’ worth of property.  Under the circumstances, evils are to be expected, and they occur.  The small owner often is crushed under the unequal assessment while the large owner comes lightly off.  Political friends are favored, political foes are made to suffer.  Even the most honest and capable of assessors find in the imperfections of the tax laws[6] an insuperable obstacle to even-handed justice.

Sec. 14. #Shifting and incidence.# The person paying a tax into the public treasury is not always the one whose income is reduced in the long run.  This is most clearly seen in the case of taxes paid by middlemen.  In most cases the final and regular burden of the tax is distributed over a number of incomes.  The passing on of the burden is called the shifting of the tax; the final location of the burden is called the incidence of the tax.  The lawmaker cannot tell exactly where the weight will fall.  The principles of value give some guidance in the inquiry, but the workings of the principle are difficult to follow.

Consider a situation where certain taxes have been for some time levied.  They have become a part of the general adjustment of prices.  If paid by any one in business they may be looked upon as a deduction from the gross proceeds or product of the business, prior to cost, or as a part of cost.[7] In either case every one choosing that business does so in the light of this fact.  Unless the business promises to yield as good incomes (wages, profits) as other lines, the number engaging in it, and the output, must diminish and thus the price of the product rise, or the cost of the factors fall, or both in some proportion.  The tax on any durative agent or on