Parfit's Moral Arithmetic and the Obligation to Obey the Law
Though consequentialist theories of political obligation have been widely criticized in recent years, a series of arguments presented by Derek Parfit, in Reasons and Persons, are now believed to have given this position new life.
Parfit and Mistakes in Moral Mathematics
In addition to the immediate and delayed fatalities and ailments following the Chernobyl explosion and the Bhopal toxic leak, numerous persons suffered allegedly imperceptible, painless, but slightly harmful effects. One question this raises is whether one ought to ignore acts causing allegedly imperceptible, but slightly harmful, effects on large numbers of persons. In Reasons and Persons ("Mistakes in Moral Mathematics," pp. 6786), Parfit argues, correctly I think, that one ought not follow "commonsense morality" and ignore acts causing such imperceptible effects on large numbers of persons.' Although his conclusion is correct, Parfit's three main arguments (used to justify his account of imperceptible effects) are highly questionable. I call these the "Mistaken Pain Defense," the "Total Effect Defense," and the "Simplicity Defense":
David Lyons on utilitarian generalization
ConclusionWe have now examined two versions of UG — that proposed by David Lyons, and a new version derived from his. Both were found to be extensionally nonequivalent to AU, but both were also found to be unacceptable moral theories (Lyons' version generated counter-intuitive prescriptions, and the derived version failed to generate any prescriptions at all in an important range of cases). Naturally, these results cannot be taken to show that no satisfactory form of UG will be forthcoming. But at least some of the conditions to be met by future proposals are now clear: any successful version of the theory must interpret the ‘generalized performance’ of an action to include only the actions of agents who face similar ranges of alternatives, and (in some cases) must select as relevant a description of the action which does not refer, either explicitly or implicitly, to the actions of other agents. Reflection shows that the same remarks hold true, mutatis mutandis, for rule utilitarianism as well: unless the rules are formulated with extreme care in these respects, they may yield unacceptable recommendations, or else fail to recommend any action at all in the very cases they are designed to resolve.17