慶応義塾大学法学部のゼミナール「伊東乾民事訴訟法研究会」の卒業生の会「乾会」による論文集。今回はテーマを民事訴訟法に限ることなく、現在関心を持っている法律分野について執筆した。.

I CATEGORIES AND PRINCIPLES ii Introductory Remarks The value of linguistics as a cognitive science lies largely in its potential for providing insights ...

Bioethics, Volume 36, Issue 4, Page 445-452, May 2022.

This article investigates the relationship among the weak Pareto principle, the strong Pareto principle, and positive responsiveness in the context of voting. First, it is shown that under a mild domain condition, if an anonymous and neutral collective choice rule (CCR) is complete and transitive, then the weak Pareto principle and the strong Pareto principle are equivalent. Next, it is shown that under another mild domain condition, if a neutral CCR is transitive, then the strong Pareto principle and positive responsiveness (...) are equivalent. By applying these results, we obtain a new characterization of the method of majority decision. (shrink)

This paper examines the concept of ‘tsunami-tendenko,’ a guideline suggesting that individuals prioritise their own safety over aiding others during large-scale disasters. Kodama defends tsunami-tendenko against accusations of egoism by arguing that the principle can be justified ethically on consequentialist (or more precisely, utilitarian) grounds. Kodama asserts that attempting to assist others during such disasters heightens the risk of ‘tomo-daore,’ where both the rescuer and the victim may perish. He claims that having people focus solely on saving themselves can maximise (...) the overall number of lives saved. However, we challenge Kodama’s assertion that utilitarianism inherently favours tsunami-tendenko over mutual assistance during disasters. Instead, this paper proposes an alternative ethical foundation for tsunami-tendenko grounded in the ‘antiextinction principle,’ which prioritises minimising the potential for catastrophic outcomes. When considering the ethics of responding to disaster, it is important to distinguish between maximising the number of lives saved (utilitarianism) and minimising the risk of tomo-daore (antiextinction principle). This distinction may be overlooked if the distribution of probabilities is not considered. We conclude that the antiextinction principle aligns more naturally with tsunami-tendenko, emphasising the avoidance of catastrophic outcomes—a concern not always addressed by utilitarianism. Therefore, tsunami-tendenko should be regarded as a societal guideline aimed at preserving community sustainability by averting total destruction. (shrink)

This paper aims to reexamine the axiom of the independence of irrelevant alternatives in the theory of social choice. A generalized notion of independence is introduced to clarify an informational requirement of binary independence which is usually imposed in the Arrovian framework. We characterize the implication of binary independence.

This paper proposes a sufficientarian theory with an interval of sufficiency levels. I assume that there are upper and lower bounds of sufficiency and that all well-being levels in between can be considered sufficiency levels. This interval reflects the vagueness of the concept of sufficiency. According to the proposed principle, a distribution is morally better than another if and only if, for each threshold within the interval, the headcount of those below the threshold under the former distribution is smaller than (...) that under the latter distribution. This necessarily leads to incommensurability in moral relations. I argue that such incommensurability makes sufficientarian principles invulnerable to some fundamental objections. (shrink)

On March 16, 2020, the Director-General of the World Health Organization said: “We have a simple message to all countries—test, test, test.” This seems like sound advice, but what if limiting the number of tests has a positive effect on infection control? Although this may rarely be the case, the possibility raises an important ethical question that is closely related to a central tension between deontological and consequentialist approaches to ethics. In this paper, we first argue that early during the (...) COVID-19 pandemic, Japan offers an interesting case because it experienced few deaths due to COVID while the number of tests was limited, suggesting that there may be cases in which low testing contributes to infection control indeed. After that, we examine deontological constraints on such a “low-testing” policy, focusing on issues related to a supposed “right to know,” which is a central issue in medical ethics in general. (shrink)

This study investigates Suzumura consistency as a condition for the rationality of social preferences. A preference is said to be Suzumura-consistent when all preference cycles include only indifference relations. This condition is equivalent to transitivity in the presence of completeness, but, in general, it is substantially weaker than transitivity when preference is incomplete. Notably, Suzumura consistency is especially significant for a preference because it is necessary and sufficient for the existence of an ordering (transitive and complete preference) that is compatible (...) with the original preference. This coherency property can be regarded as a requirement for potential rationality. In this study, we examine the implications of shifting from actual rationality to potential rationality in collective decision-making. We introduce the concept of an alternative-dependent coherent collection in order to obtain a representation of a class of Suzumura-consistent collective choice rules that satisfy the axioms imposed in Arrow’s impossibility theorem. This demonstrates that the power structure to determine social choice can be alternative-dependent. (shrink)

This paper offers a new insight on the Condorcet Jury Theorem (CJT) in the theory of epistemic democracy. This theorem states that democratic decision-making leads us to correct outcomes under certain assumptions. One key assumption is the ‘independence condition’, which requires that voters form their beliefs independently when they vote. This paper examines the role of an opinion leader as an informational source, which potentially violates independence. We demonstrate that voters’ beliefs may be correlated in the presence of the leader, (...) and that the CJT can fail if the leader’s opinions are reliable. This leads us to the following paradoxical observation: for epistemic democracy, good leaders may be bad, while bad leaders may be good. (shrink)

The Trends in International Mathematics and Science Study found that even though children from all East Asian countries outperformed American children, American students reported higher self-evaluation of their math and science abilities than did students from East Asian countries such as China, Korea, and Japan (Mullis, Martin, Gonzalez, & Chrostowski, 2004). Such cross-cultural differences in self-appraisal fit the stereotype of the modest East Asian and contribute to the received view that East Asians have less positive self-concepts than Americans. This view (...) was summarized recently by Heine, Lehman, Markus, and Kitayama (1999) as follows: ‘‘The need for positive self-regard, as it is currently conceptualized, is not a universal, but rather is rooted in significant aspects of North American culture’’ (p. 766; but cf. Sedikides, Gaertner, & Vevea. (shrink)

Since Condorcet discovered the voting paradox in the simple majority rule, many scholars have tried to investigate conditions that yield “social-preference cycles”. The paradox can be extended to two main approaches. On the one hand, Kenneth Arrow developed a general framework of social choice theory; on the other hand, direct generalizations of the paradox were offered. The motivation and surface meaning of the two approaches are different, as are the assumed background conditions. In this paper, we investigate the relationship between (...) the two approaches by taking a close look at two works, Ferejohn and Fishburn and Schwartz. (shrink)

In this study, we propose a new direction of research on the axiomatic analysis of approval voting, which is a common democratic decision method. Its novelty is to examine an infinite population setting, which includes an application to intergenerational problems. In particular, we assume that the set of the population is countably infinite. We provide several extensions of the method of approval voting for this setting. As our main result, axiomatic characterizations of the extensions are offered by revealing a direct (...) link between approval voting and the Borda rule. The characterized methods are natural extensions of the standard approval voting method for the finite-population case and are regarded as minimum requirements for other possible infinite-population extensions, which are reasonably democratic. (shrink)

This paper examines collective decision-making with an infinite-time horizon setting. First, we establish a result on the collection of decisive sets: if there are at least four alternatives and Arrow’s axioms are satisfied on the selfish domain, then the collection of decisive sets forms an ultrafilter. Second, we impose generalized versions of stationarity axiom for social preferences, which are substantially weaker than the standard version. We show that if any of our generalized versions are satisfied in addition to Arrow’s axioms, (...) then some generation is dictatorial. Moreover, we specify a very weak stationarity axiom that guarantees a possibility result. (shrink)

This paper examines social choice theory with the strong Pareto principle. The notion of conditional decisiveness is introduced to clarify the underlying power structure behind strongly Paretian aggregation rules satisfying binary independence. We discuss the various degrees of social rationality: transitivity, semi-transitivity, the interval-order property, quasi-transitivity, and acyclicity.

L’imposition est l’un des principaux sujets de la théorie de la propriété des droits, mais il a pourtant été assez négligé jusque récemment. La communauté académique des philosophes avance de nos jours des arguments pour discuter avec ardeur des types d’imposition qui sont légitimes, s’il en est, et l’on doit beaucoup en ce domaine à l’ouvrage de Liam Murphy et Thomas Nagel The Myth of Ownership. Dans leur ouvrage polémique, les auteurs soutiennent qu’il n’existe pas de droit légitime permettant d’imposer (...) par préemption ni la propriété ni les droits naturels à la propriété et que le processus d’imposition n’empiète certes jamais sur les droits de propriété, qui sont le fruit d’une institution par décret gouvernemental. Murphy et Nagel prennent pour cible principale Richard Epstein qui prône une vue libertarienne ou « libérale classique » contraire à ce propos. Epstein compare l’imposition à une expropriation publique et argumente en faveur de l’impôt sur le revenu. Nous discutons ici la thèse d’Epstein sur la propriété privée, avec laquelle nous nous trouvons en accord quoique moyennant des nuances notables. Nous examinons la théorie étatiste de la propriété de Murphy et Nagel et nous soutenons que leur égalitarisme est surtout le fait d’un présupposé. Nous concluons que l’impôt sur la propriété foncière est la forme d’imposition la plus apte à être légitimée à partir de la perspective libertarienne sur les droits naturels, plus en tous cas que l’impôt sur le revenu et que la taxe sur la valeur ajoutée, formes d’impôt qui sont les plus habituelles. Surtout, nous soutenons qu’il y a là une forme d’imposition que la Constitution du Japon autorise. (shrink)

We examine the range of anonymity that is compatible with a Paretian social welfare relation (SWR) on infinite utility streams. Three alternative coherence properties of an SWR are considered, namely, acyclicity, quasi-transitivity, and Suzumura consistency. For each case, we show that a necessary and sufficient condition for a set of permutations to be the set of permissible permutations of some Paretian SWR is given by the cyclicity of permutations and a weakening of group structure. Further, for each case of coherence (...) property, we show that the extended Pareto rule is the least element of the class of anonymous Paretian SWRs. (shrink)

We examine a general class of variable-value population principles. Our particular focus is on the extent to which such principles can avoid the repugnant and sadistic conclusions. We show that if a mild limit property is imposed, avoidance of the repugnant conclusion implies the sadistic conclusion. This result generalizes earlier observations by showing that they apply to a substantially larger class of principles. Our second theorem states that, under the limit property, the axiom of mere addition also conflicts with avoidance (...) of the repugnant conclusion. This result is a consequence of a similar observation that appears in the earlier literature. (shrink)

「語の意味」とは何か?『類語大辞典』の編集・執筆に関わってきた著者が、「意味の本質」「同義・類義・多義」「意味記述の方法」「辞書と意味記述」の4部に渡って、これまで深めてきた考察を明らかにする、「こと ばの意味」の研究に大きく資する一冊。.

Journal of Political Philosophy, EarlyView.

Journal of Political Philosophy, EarlyView.