The Logic of Normative Justification

Abstract

What really makes the concepts of obligation or permission so important for practical philosophy? What if we could find a better concept, one that, despite the simplicity, could show itself as intuitive and rich as possible? Could justifications be used in common language and practice as a sign of ethical judgment and as a strong motive for action? In most scenarios, for example, it really doesn’t matter if a given action is obliged, permitted or forbidden, one may perform the action as long as a justification for doing it is present. In this sense, the notion of justification seems to be more basic and powerful than other concepts used in the philosophical discourse. The existence of formal systems based on the epistemological side of justification, created by Artemov, led us primarily to think that justification could make the formal discourse much more accurate for ethics than the ones using deontological concepts. In the semantical and syntactical aspects, almost all of Artemov’s systems directly proved to be fruitful for ethical purposes. We also developed combinations between the standard deontic logic and logics of justification, resulting in what whe called the Logics of Normative Justification. These systems were able to change the object of the justification formulas and shed some light in ethics as a whole, normative and metaethics. Metaethics were a forgotten subject in formal ethics. We were also able to deal with some known problems in deontic logic, like the famous Ross’s paradox and the expressiveness of prima facie and all-things-considered obligations.

Keywords

• Deontic logic,modality,justification,ethics,metaethics

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