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Showing papers on "Normal modal logic published in 1970"


Book ChapterDOI
01 Jan 1970
TL;DR: The present author has been noting the confusions, misdirections of emphasis, and duplications of effort current in studies of modal logic and is anxious to disseminate all kinds of valuable advice on the subject.
Abstract: Everyone knows how much more pleasant it is to give advice than to take it. Everyone knows how little heed is taken of all the good advice he has to offer. Nevertheless, this knowledge seldom restrains anyone, least of all the present author. He has been noting the confusions, misdirections of emphasis, and duplications of effort current in studies of modal logic and is, by now, anxious to disseminate all kinds of valuable advice on the subject. Thus he is very happy that the Irving meeting has provided such a suitable and timely forum and hopes that all this advice can provoke some useful discussion — at least in self-defense. The time really seems to be ripe for a fruitful development of modal logic, if only we take care to purify and simplify the foundations. A quite flexible framework is indeed possible: the old puzzles can be brushed aside, and one can begin to provide meaningful applications.

310 citations


Book ChapterDOI
01 Jan 1970
TL;DR: Deontic logic as mentioned in this paper is defined as the study of those sentences in which only logical words and normative expressions occur essentially, and sentences involving them are called deontic sentences, and is closely related to logic of imperatives (or the logic of commands).
Abstract: The word ‘deontic’ is derived from the Greek word ‘δeoυτως’, which may be translated ‘as it should be’ or ‘duly’. Bentham uses ‘deontology’ for “the science of morality”, and Ernst Mally [30] was the first to use the term — in the form Deontik — to refer to logical study of the normative use of language. In accordance with Bolzano and Quine’s definition of logical truth, deontic logic can be defined as the study of those sentences in which only logical words and normative expressions occur essentially.1 Normative expressions include the words ‘obligation’, ‘duty’, ‘permission’, ‘right’, and related expressions. These expressions may be termed deontic words, and sentences involving them deontic sentences.2 A deontic sentence is a truth of deontic logic if it is true and remains true for all variations of its non-logical and non-deontic words (that is, expressions which are not logical or deontic words). Deontic logic is closely related to the logic of imperatives (or the logic of commands); in fact, many authors regard these fields as essentially the same.3 What is here called deontic logic has also been referred to as logic of obligation and logic of norms (or logic of normative systems).4

160 citations


Book ChapterDOI
01 Jan 1970
TL;DR: The uppercase letters A, B, C, …, Q, R, … are used as place-holders for expressions denoting various predicates or attributes of (human) acts.
Abstract: 1 In deontic logic, we must be able to discuss various predicates or attributes (properties and relations) of (human) acts As place-holders for expressions denoting such predicates, we shall in this paper use the uppercase letters A, B, C, …, Q, R, … The reader may think of them as standing for some (unspecified) properties and relations of human acts It is important to realize, and to keep in mind, that these letters do not represent individual acts, but stand for certain general characteristics of such act-individuals (or for general characteristics of n-tuples of such individual acts)

72 citations


Book ChapterDOI
01 Oct 1970-Synthese
TL;DR: This essay attempts to provide a rationale for the non-standard semantical system of the authors' by formulating some proto-philosophical data that both guide the development of the system and serve as tests of adequacy for it.
Abstract: Deontic concepts like ought, right, obligation, forbidden, and permissible have benefited from the philosophically exciting work in the semantics of modal concepts done by Kanger1, Hintikka2, Kripke3, Montague4 and others. Their semantics illuminates both the topic and the contribution of the standard axiomatic approach to deontic logic: the topic is what philosophers used to call the Ought-to-be. On the other hand, the nonstandard approach represented by early axiomatic deontic systems of ours deals with the Ought-to-do. Thus, rather than competing with the standard approach to deontic logic, our non-standard approach complements it. This can, however, be seen only by providing our nonstandard approach with a minimum of semantical foundations. This is precisely what this essay attempts to do. We shall also provide a rationale for our non-standard semantical system by formulating some proto-philosophical data that both guide the development of the system and serve as tests of adequacy for it. In fact, our concern is primarily philosophical, not technical.

41 citations