Another attempted criterion of just taxation was the subject of a flourishing literature for many decades, although it is now decidedly going out of fashion. The many variants of the “sacrifice” approach are akin to a subjective version of the “ability-to-pay” principle.

The benefit principle differs radically from the two preceding criteria of taxation. For the sacrifice and ability-to-pay principles depart completely from the principles of action and the accepted criteria of justice on the market. On the market people act freely in those ways which they believe will confer net benefits upon them. The result of these actions is the monetary exchange system, with its inexorable tendency toward uniform pricing and the allocation of productive factors to satisfy the most urgent demands of all the consumers.

Equality of taxation has far more to commend it than any of the above principles, none of which can be used as a canon of taxation. “Equality of taxation” means just that—a uniform tax on every member of the society. This is also called a head tax, capitation tax, or poll tax. (The latter term, however, is best used to describe a uniform tax on voting, which is what the poll tax has become in various American states.) Each person would pay the same tax annually to the government.

A slogan popular among many “right-wing” economists is that taxation should be for “revenue only,” and not for broad social purposes. On its face, this slogan is simply and palpably absurd, since all taxes are levied for revenue. What else can taxation be called but the appropriation of funds from private individuals by the State for its own purposes? Some writers therefore amend the slogan to say: Taxation should be limited to revenue essential for social services. But what are social services?

We have thus analyzed all the alleged canons of tax justice. Our conclusions are twofold: (1) that economics cannot assume any principle of just taxation, and that no one has successfully established any such principles; and (2) that the neutral tax, which seems to many a valid ideal, turns out to be conceptually impossible to achieve. Economists must therefore abandon their futile quest for the just, or the neutral, tax.

Of all the patterns of tax distribution, the progressive tax has generated the most controversy. In the case of the progressive tax, the conservative economists who oppose it have taken the offensive, for even its advocates must grudgingly admit that the progressive tax lowers incentives and productivity. Hence, the most ardent champions of the progressive tax on “equity” grounds admit that the degree and intensity of progression must be limited by considerations of productivity.

We have refuted elsewhere the various arguments that form part of the Henry Georgist edifice: the idea that “society” owns the land originally and that every new baby has a “right” to an aliquot part; the moral argument that an increase in the value of ground land is an “unearned increment” due to external causes; and the doctrine that “speculation” in sites wickedly withholds productive land from use.

For centuries before the science of economics was developed, men searched for criteria of the “just price.” Of all the innumerable, almost infinite possibilities among the myriads of prices daily determined, what pattern should be considered as “just”? Gradually it came to be realized that there is no quantitative criterion of justice that can be objectively determined. Suppose that the price of eggs is 50¢ per dozen, what is the “just price”?