How very different were the efficiency gods of 1938! How I long to sacrifice intellectual property to those gods, as once were slain private bridges and railroads on their art deco altars.
The idea that all will be for the best if only competition exists is a heritage from the economic theory of Adam Smith, built up at a time when agriculture was still the dominant economic activity. The typical agricultural situation is one of rising marginal costs. Free competition, of the type that has usually existed in agriculture, leads to sales at marginal cost, if we now abstract the effects of weather and other uncertainty, which are irrelevant to our problem. Since we have seen that sales at marginal cost are a condition of maximum general welfare, this situation is a satisfactory one so far as it goes. But the free competition associated with agriculture, or with unorganized labor, is not characteristic of enterprises such as railroads, electric-power plants, bridges, and heavy industry. It is true that a toll bridge may be in competition with other bridges and ferries; but it is a very different kind of competition, more in the nature of duopoly. To rely on such competition for the efficient conduct of an economic system is to use a theorem without observing that its premises do not apply. Free competition among toll-bridge owners, of the kind necessary to make the conclusion applicable, would require that each bridge be parallelled by an infinite number of others immediately adjacent to it, all the owners being permanently engaged in cutthroat competition. If the marginal cost of letting a vehicle go over a bridge is neglected, it is clear that under such conditions the tolls would quickly drop to zero and the owners would retire in disgust to allow anyone who pleased to cross free.
The efficient way to operate a bridge — and the same applies to a railroad or factory, if we neglect the small cost of an additional unit of product or of transportation — is to make it free to the public, so long at least as the use of it does not increase to a state of overcrowding. A free bridge costs no more to construct than a toll bridge, and costs less to operate; but society, which must pay the cost in some way or other, gets far more benefit from the bridge if it is free, since in this case it will be more used. Charging a toll, however small, causes some people to waste time and money in going around by longer but cheaper ways, and prevents others from crossing. The higher the toll, the greater is the damage done in this way; to a first approximation, for small tolls, the damage is proportional to the square of the toll rate, as Dupuit showed. There is no such damage if the bridge is paid for by income, inheritance, and land taxes, or for example by a tax on the real estate benefited, with exemption of new improvements from taxation, so as not to interfere with the use of the land. The distribution of wealth among members of the community is affected by the mode of payment adopted for the bridge, but not the total wealth, except that it is diminished by bridge tolls and other similar forms of excise. This is such plain common sense that toll bridges have now largely disappeared from civilized communities. But New York City’s bridge and tunnels across the Hudson are still operated on a toll basis, because of the pressure of real estate interests anxious to shift the tax burden to wayfarers, and the possibility of collection considerable sums from persons who do not vote in the city.Harold Hotelling, The General Welfare in Relation to Problems of Taxation and of Railway and Utility Rates, 6 Econometrica 260-61 (1938).