The Dualism of Practical Reason: The Profoundest Problem of ethics


  • Cinara Nahra Universidade Federal do Rio Grande do Norte, Natal, R. N.



Dualism of practical reason, Dual source view, Altruism, Egoism


The aim of this article is to discuss and revisit what Sidgwick called the profoundest problem of ethics: the dualism of practical reason. I argue that Crisp’s dual source view provides a good solution for the dualism via the small cost principle showing that we have to balance agent relative and agent neutral reason in a kind of a rational “negotiation” between our egoistic and our altruistic motivations. I suggest, however, that in order to justify his solution it is necessary to go beyond Sidgwick establishing a limit for the acceptance of egoism as a legitimate method of ethics. I propose also that the dualism is not only the profoundest problem of ethics, but also one of the more serious, it is the biggest contemporary ethical puzzle of humankind, and whose practical solution is of paramount importance for the future of life on earth.



Biografia do Autor

Cinara Nahra, Universidade Federal do Rio Grande do Norte, Natal, R. N.

Possui graduação (bacharelado) em filosofia pela Universidade Federal do Rio Grande do Sul (1987), mestrado em filosofia pela Universidade Federal do Rio Grande do Sul (1994) na área de filosofia moral e politica, e doutorado (phd) em filosofia, na área de ética, politica e politicas publicas (ethics, politics and public policies) pela University of Essex (2005) onde foi orientada pelo Prof. Tom Sorell. Professora associada do Departamento de Filosofia da Universidade Federal do Rio Grande do Norte (UFRN) onde atua desde 1995. Atua especialmente na área de ética e filosofia moral, discutindo autores da filosofia moral como Kant, Mill e temas como ética de princípios, ética utilitarista, deontoutilitarismo, neuroetica, enhancement, moral enhancement, ética e política, preconceito, moralismo, sexualidade e procriação (especialmente as questões morais envolvidas no aborto, na homossexualidade e na prostituição) ética aplicada e bioética. Autora de livros como Malditas Defesas Morais (Cooperativa Cultural/UFRN), Uma Introdução a Filosofia Moral de Kant (EDUFRN).e co-autora de livros como Através da Lógica (Vozes) e Body and Justice (Cambridge Scholars Publishing)


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