‘Must’, ‘Ought’ and the Structure of Standards

Authors

Gunnar Björnsson
Robert Shanklin, Santa Clara UniversityFollow

Document Type

Conference Proceeding

Publication Date

2014

Publisher

Springer

Abstract

This paper concerns the semantic difference between strong and weak necessity modals. First we identify a number of explananda: their well-known intuitive difference in strength between ‘must’ and ‘ought’ as well as differences in connections to probabilistic considerations and acts of requiring and recommending. Here we argue that important extant analyses of the semantic differences, though tailored to account for some of these aspects, fail to account for all. We proceed to suggest that the difference between ’ought’ and ’must’ lies in how they relate to scalar and binary standards. Briefly put, must(ϕ) says that among the relevant alternatives, ϕ is selected by the relevant binary standard, whereas ought(ϕ) says that among the relevant alternatives, ϕ is selected by the relevant scale. Given independently plausible assumptions about how standards are provided by context, this explains the relevant differences discussed.

Chapter of

Deontic Logic and Normative Systems

Part of

Lecture Notes in Computer Science

Comments

12th International Conference, DEON 2014, Ghent, Belgium, July 12-15, 2014.

Recommended Citation

Björnsson, G., & Shanklin, R. (2014). ‘Must’, ‘Ought’ and the Structure of Standards. In F. Cariani, D. Grossi, J. Meheus, & X. Parent (Eds.), Deontic Logic and Normative Systems (pp. 33–48). Springer International Publishing. https://doi.org/10.1007/978-3-319-08615-6_4