In this paper, I will discuss boulesic and deontic logic and the relationship between these branches of logic. By ‘boulesic logic,’ or ‘the logic of the will,’ I mean a new kind of logic that deals with ‘boulesic’ concepts, expressions, sentences, arguments and systems. I will concentrate on two types of boulesic expression: ‘individual x wants it to be the case that’ and ‘individual x accepts that it is the case that.’ These expressions will be symbolised by two sentential operators that take individuals and sentences as arguments and give sentences as values. Deontic logic is a relatively well-established branch of logic. It deals with normative concepts, sentences, arguments and systems. In this paper, I will show how deontic logic can be grounded in boulesic logic. I will develop a set of semantic tableau systems that include boulesic and alethic operators, possibilist quantifiers and the identity predicate; I will then show how these systems can be augmented by a set of deontic operators. I use a kind of possible world semantics to explain the intended meaning of our formal systems. Intuitively, we can think of our semantics as a description of the structure of a perfectly rational will. I mention some interesting theorems that can be proved in our systems, including some versions of the so-called hypothetical imperative. Finally, I show that all systems that are described in this paper are sound and complete with respect to their semantics.
The paper points to problems that stem from the fact that theories subsumed under the heading ''deontic logic'' often have unclearly defined goals and their creators tend to conflate perspectives that are discordant. It suggests that many problems that have troubled deontic logic for many years can be better grasped (and in some cases in effect solved) if we properly parcel out the area of logical studies subsumed under the heading ''deontic logic''. Prescriptive language games proposed by David Lewis together with his conception of scorekeeping in the games are proposed as a suitable starting point for the parceling. Using the perspective of the games we can distinguish different theories to be developed within deontic logic. They differ in their focus on different kinds of moves in the language game and in their conceiving the language game either as static or as dynamic., Příspěvek poukazuje na problémy, které vyplývají ze skutečnosti, že teorie obsažené pod nadpisem ,,deontická logika'' mají často nejasně definované cíle a jejich tvůrci mají tendenci sjednotit perspektivy, které jsou neslučitelné. Naznačuje, že mnoho problémů, které mají mnoho let problémy s deontickou logikou, lze lépe pochopit (a v některých případech i účinně řešit), pokud řádně rozložíme oblast logických studií zahrnutých pod nadpisem ,,deontická logika''. Předpisové jazykové hry navržené Davidem Lewisem spolu s jeho pojetím skóre ve hrách jsou navrženy jako vhodný výchozí bod pro balíčkování. Pomocí perspektivy her můžeme rozlišit různé teorie, které mají být vyvinuty v rámci deontické logiky., and Vladimír Svoboda