Abstract

This study offers an analysis of sentences of conditional and unconditional obligation within which the major paradoxes of deontic logic are resolved. ;Chapter two outlines the proof theory and formal and informal semantics of standard deontic logic. In the next chapter two variants of Chisholm's paradox of conditional obligation are discussed in detail. It is argued that a solution to this paradox rests upon the development of a defensible account of factual detachment. Arguments are offered against the validity of both Mott's and al-Hibri's unrestricted factual detachment rule as well as Greenspan's temporally grounded treatment of detachment. In chapter four a comprehensive and original account of factual detachment is presented which resolves each variant of Chisholm's paradox from both an intuitive and formal perspective. The guiding principle behind this account is that the admissibility of detaching an unconditional sentence OA from a conditional sentence O is a function of both the truth values and the normative status of certain subsentences of O. ;The apparatus developed to this point is applied to the resolution of three minor deontic paradoxes in chapter five--the Good Samaritan paradox, Ross's paradox, and the John and Suzy paradox. The work closes in the sixth chapter with a discussion of formal problems of conditionality. Considerations are brought forward against formally defining conditional obligation sentences in terms of a fusion of a monadic obligation operator and a non-classical, non-deontic conditional connective. Instead, a simple selection function semantics for conditional obligation is offered in terms of a primitive dyadic obligation operator