This chapter examines how this semantic account can be developed in order to enable it to deal with some other semantic issues. First, this account can give a good account of deontic logic (the logic of ‘ought’). Secondly, it can explain the way in which terms like ‘ought’ are systematically context-sensitive and express different concepts in different contexts of utterance. Finally, it can explain the logical relations between ‘ought’ and ‘best’: for every sense of ‘ought’ there is a corresponding sense of ‘best’, such that something ought to be the case if and only if it is necessary for the best state of affairs. Because the relevant sorts of ‘ought’ and ‘best’ are systematically context-sensitive, this logical relationship between ‘ought’ and ‘best’ does not entail any controversial sort of consequentialist or teleological theory.
Keywords: deontic logic, context-sensitivity, concepts, best, consequentialist, teleological