The Twin Earth thought experiment invites us to consider a liquid that has all of the superficial properties associated with water (clear, potable, etc.) but has entirely different deeper causal properties (composed of “XYZ” rather than of H2O). Debates about natural kind concepts have sought to accommodate an apparent fact about ordinary people's judgments: Intuitively, the Twin Earth liquid is not water. We present results showing that people do not have this intuition. Instead, people tend to judge that there is (...) a sense in which the liquid is not water but also a sense in which it is water. (shrink)

The Twin Earth thought experiment invites us to consider a liquid that has all of the superficial properties associated with water (clear, potable, etc.) but has entirely different deeper causal properties (composed of “XYZ” rather than of H2O). Although this thought experiment was originally introduced to illuminate questions in the theory of reference, it has also played a crucial role in empirically informed debates within the philosophy of psychology about people’s ordinary natural kind concepts. Those debates have sought to accommodate (...) an apparent fact about ordinary people’s judgments: Intuitively, the Twin Earth liquid is not water. We present results from four experiments showing that people do not, in fact, have this intuition. Instead, people tend to have the intuition that there is a sense in which the liquid is not water but also a sense in which it is water. We explore the implications of this finding for debates about theories of natural kind concepts, arguing that it supports views positing two distinct criteria for membership in natural kind categories – one based on deeper causal properties, the other based on superficial, observable properties. (shrink)

How can one person’s having political power over another be justified? This essay explores the idea that such justifications must be in an important sense derivative, and that this ‘Derivative Justification Constraint’ bars certain justifications widely endorsed in political and philosophical debates. After critically discussing the most prominent extant articulations of the Constraint (associated with a view often called ‘political instrumentalism’), the essay offers a novel account of what precisely the Constraint bars (in short: justification by appeal to non-derivative goods (...) that include among their elements one person’s ruling over another), what motivates it (in a nutshell: a deeply non-instrumental concern for each person’s moral independence), and what it entails for how we may justify democratic political arrangements in particular. (shrink)

¿Puede la tesis del reemplazo de Raz sobrevivir en el contexto de una teoría dworkiniana del derecho y de la adjudicación? Judging Positivism, de Margaret Martin, fornece una de las mejores reconstrucciones y una de las más interesantes críticas ya planteadas contra la influyente filosofía del derecho de Joseph Raz. En uno de los pasos centrales de su argumento, Martin desafía una sumisión central de Raz, que es el intento de combinar la tesis del reemplazo con la tesis de la (...) justificación normal. Mientras la primera exige que ciudadanos y oficiales excluyan de la deliberación cualesquiera razones de primer orden para la acción, la ultima invita consideraciones sobre legitimidad que no se puede examinar con independencia de las razones de primer orden que la tesis del remplazo pretende excluir. En este comentario crítico, yo acepto la crítica de Martin según la cual esas dos tesis no pueden ser aceptadas como argumentos conceptuales. Sin embargo, sugiero que aún existe un espacio para armonizarlas si se las acepta por razones normativas. Si hay un buen argumento para tratar razones jurídicas como un nivel intermedio de razones para la acción, entonces puede haber buenos argumentos circunstanciales para tratar razones institucionales como remplazantes en el sentido que Raz defiende en su teoría del derecho. (shrink)