An Intuitionistic Reformulation of Mally’s Deontic Logic
- 166 Downloads
In 1926, Ernst Mally proposed a number of deontic postulates. He added them as axioms to classical propositional logic. The resulting system was unsatisfactory because it had the consequence that A is the case if and only if it is obligatory that A. We present an intuitionistic reformulation of Mally’s deontic logic. We show that this system does not provide the just-mentioned objectionable theorem while most of the theorems that Mally considered acceptable are still derivable. The resulting system is unacceptable as a deontic logic, but it does make sense as a lax logic in the modern sense of the word.
KeywordsDeontic logic Intuitionistic logic Lax logic
Unable to display preview. Download preview PDF.
- 2.Føllesdal, D., & Hilpinen, R. (1981). Deontic logic: An introduction. In R. Hilpinen (Ed.), Deontic logic: Introductory and systematic readings (2nd ed., pp. 1–35). Dordrecht: Reidel.Google Scholar
- 4.Lokhorst, G.J.C., & Goble, L. (2004). Mally’s deontic logic. Grazer Philosophische Studien, 67, 37–57.Google Scholar
- 5.Mally, E. (1926). Grundgesetze des Sollens: Elemente der Logik des Willens. Graz: Leuschner und Lubensky.Google Scholar
- 7.Menger, K. (1939). A logic of the doubtful: On optative and imperative logic. In Reports of a Mathematical Colloquium (2nd series, 2nd issue, pp. 53–64). Notre Dame: Indiana University Press.Google Scholar
- 8.Morscher, E. (1998). Mallys Axiomsystem für die deontische Logik: Rekonstruktion und kritische Würdigung. In A. Hieke (Ed.), Ernst Mally: Versuch einer Neubewertung (pp. 81–165). Sankt Augustin: Academia.Google Scholar