Praxis

In Nomoi 915d-e, for instance, it is decreed that all sales must take place in the official market, by the vendor in his allotted space. Sales occur under the special protection of the state, so that the buyer is protected, for example, from purchasing goods with hidden damage.

According to Nomoi 916a-d, if a sold slave turns out to be physically or mentally sick, the sale may be revoked - unless the buyer has a specialist knowledge of humans, such as a physician or an athletics coach. It is thus made clear that not all parties to a contract are the same - this is the interest­ing feature in our context, not the slave trade. The nineteenth-century insistence on the fictional equality of all parties to a contract is thus superseded by a realistic differentiation based on professional expertise, and the responsibility is allotted to the party which most easily commands that expertise. In con­temporary German private law (for example, §§ 459ff. BGB), no such differentiation is made. In that sense, the Nomoi are - from a law and economics perspective - more advanced than the 2300-year younger codification, since the telos of the provision, which ultimately is the smooth flow of commerce, is much better ensured by Plato.

Nomoi 937d-938c deals with litigious lawyers who try to persuade people to sue, even if there is no good case. The mildest punishment for such behaviour is to be forbidden to sue for a certain period. Lawyers who are citizens and who have been found by a court to have frivolously sued twice for sheer fun, or once out of greed, even risk capital punishment. This seems outrageously harsh today, although theoretically, that is, if it does not concern one’s own lawyer, it might be possible to find many who would agree with this measure. But regarding the severity of the punishment, one should re­member the utopian quality of the Nomoi. This provision is a necessary realist corrective because the Nomoi have a system of ‘punitive damages’: double, or, more rarely, triple the worth of items in question, payable to the victorious party (see, for example, Nomoi 916b-d, 921c, 928b) Thus, the incentive for frivolous suits is very high, and without the corrective measures advocated in this section, the system might not work very well. Noticeable here is Plato’s interest in procedure and the influence that procedure has on substance; this is a key law and economics feature.

Nomoi 849e-850a, mostly known for advocating the prohibition of (domestic) trade gain, and often referred to as ‘anti-capitalist’, also contains what can be interpreted contrariwise, namely, as an almost Coasean concern with the efficient regulation of the market over government intervention, even if the goal is ‘anti-capitalist’. Plato wants to exclude from the polis any form of credit sale - ‘Nobody shall give to another anything in advance’ (844e; on Plato and credit, see Klingenberg, 1982). However, similar to 915d-e (above), this is not achieved by state regulation or intervention, but by the opposite, that is, the exclusion of state intervention in the case of non-payment of the debt: ‘Or, if he necessarily has the trust in the other, he has to be satisfied whether he receives that what is his or not, because he may not draw legal claims from such an action’ (849e-850a).

In Nomoi 844a-d, the passage on water supply - probably based on histori­cal examples, as it explicitly claims (844a; Haliste, 1950, 143-4) - it is decreed that, if someone with land elevated higher than that of his neighbour has too much water on his land because of rain, he must agree with the latter on how to let the water flow away so that it creates the least damage for either party (844c; Haliste, 1950: 147-9). An official is asked to intervene only if an agreement cannot be reached, (844c-d) - and that is certainly not historical, but Platonic.

One of the central achievements of Coase’s ‘The problem of social cost’, arguably the foundational work of modern law and economics, is to demon­strate that the Pigouvian tax, which internalizes externalities by, for example, charging a polluting industrial plant for the costs of pollution, is not neces­sarily economically efficient, because ‘taxing the generator of the externality in a measure corresponding to the difference between the private cost and the social cost of his own activity [fails] to consider the effects of potential victims’ behaviour’ (Parisi, Chapter 1 in this volume; see Coase, 1960: 2). The motive of Nomoi 844c is thus clearly Coasean, that is, the owner of the less elevated land in Plato’s case is not, or not only, a victim, because without him, there would be no problem at all. ‘The problem is to avoid the more serious loss’, as Coase says (1960, 2), and that must be Plato’s motive as well.