gert-jan Lokhorst

Delft University of Technology | TU · Philosophy Section

Alan Ross Anderson was one of the first logicians who were interested in the logic of prudence and related concepts, such as caution. He called this area “eubouliatic logic,” a term which has not become popular. Anderson made a distinction between four prudence-related concepts which can be placed in a square of opposition. Prudence and related con...

Some years ago, Lokhorst proposed an intuitionistic reformulation of Mally's deontic logic (1926). This reformulation was unsatisfactory, because it provided a striking theorem that Mally himself did not mention. In this paper, we present an alternative reformulation of Mally's deontic logic that does not provide this theorem.

We discuss three aspects of the intuitionistic reformulation of Mally’s deontic logic that was recently proposed (Journal of Philosophical Logic 42, 635–641, (2013)). First, this reformulation is more similar to Standard Deontic Logic than appears at first sight: like Standard Deontic Logic, it is Kanger reducible and Anderson reducible to alethic...

In 1926, Ernst Mally proposed a number of deontic postulates. He added them as axioms to classical propositional logic. The resulting system was unsatisfactory because it had the consequence that A is the case if and only if it is obligatory that A. We present an intuitionistic reformulation of Mally’s deontic logic. We show that this system does n...

The latest version of the entry "Philosophy of Technology" may be cited via the earliest archive in which this version appears: Franssen, Maarten, Lokhorst, Gert-Jan and van de Poel, Ibo, "Philosophy of Technology", The Stanford Encyclopedia of Philosophy (Fall 2018 Edition), Edward N. Zalta (ed.), URL = <https://plato.stanford.edu/archives/fall20...

It has been argued that ethically correct robots should be able to reason about right and wrong. In order to do so, they must have a set of do’s and don’ts at their disposal. However, such a list may be inconsistent, incomplete or otherwise unsatisfactory, depending on the reasoning principles that one employs. For this reason, it might be desirabl...

This is a report on the 3-day workshop "The Neuroscience of Responsibility" that was held in the Philosophy Department at Delft University of Technology in The Netherlands during February 11th-13th, 2010. The workshop had 25 participants from The Netherlands, Germany, Italy, UK, USA, Canada and Australia, with expertise in philosophy, neuroscience,...

It has been argued that ethically correct robots should be able to reason about right and wrong. In order to do so, they must have a set of do’s and don’ts at their disposal. However, such a list may be inconsistent, incomplete or otherwise unsatisfactory, depending on the reasoning principles that one employs. For this reason, it might be desirabl...

When thinking about ethics, technology is often only mentioned as the source of our problems, not as a potential solution to our moral dilemmas. When thinking about technology, ethics is often only mentioned as a constraint on developments, not as a source and spring of innovation. In this paper, we argue that ethics can be the source of technologi...

This chapter discusses some recent work in the artificial intelligence and law community on the logic of mens rea ascriptions. It extends this work to give an account of quantified mens rea ascriptions in the sense in which they have been discussed in the legal literature. It studies the consequences of this work for neuroscience. The chapter argue...

In 1926, Ernst Mally proposed the first system of deontic logic. His system turned out to be unacceptable. How can it be repaired? We discuss several proposals to reformulate it in terms of strict implication, relevant implication and strict relevant implication.

Tractatus 5.542–5.5421 should be read as follows: anything which represents is complex; the soul is simple; so ‘the superficial psychologists of the present day’ are mistaken when claiming that the soul represents anything. In contrast to the ‘empirical self’, with which psychology is concerned, the ‘metaphysical’ or ‘transcendental’ soul, subject,...

We present axiomatizations of the deontic fragment of Anderson's relevant deontic logic (the logic of obligation and related concepts) and the eu- bouliatic fragment of Anderson's eubouliatic logic (the logic of prudence, safety, risk, and related concepts).

Several systems of monadic deontic logic are dened in terms of systems of alethic modal logic with a propositional constant. When the universal propositional quantier is added to these systems, the propo- sitional constant becomes denable in terms of the deontic operator. As a result, the meaning of this constant becomes clearer and it becomes easy...

We present a new axiomatization of the deontic fragment of Anderson's relevant deontic logic, give an Andersonian reduction of a relevant version of Mally's deontic logic previously discussed in this journal, study the effect of adding propositional quantification to Anderson's system, and discuss the meaning of Anderson's propositional constant in...

Zo'n twintig jaar geleden schreef ik een boekje, Brein en bewustzijn, waarin ik de filosofische theorieën van moderne hersenonderzoekers tegen het licht hield en concludeerde dat deze over het algemeen veel te wensen overlaten. Filosofisch amateurisme bleek in deze kringen hoogtij te vieren en de geest van Descartes, de zeventiende-eeuwse filosoof...

In 1926, Mally presented the first formal system of deontic logic. His system had several consequences which Mally regarded as surprising but defensible. It also, however, has the consequence that A is obligatory if and only if A is the case, which is unacceptable from the point of view of any reasonable deontic logic. We describe Mally's system an...

We provide a description and informal analysis of the commonalities in moral discourse concerning issues in the field of information and communications technology, present a logic model (DEAL) of this type of moral discourse that makes use of recent research in deontic, epistemic, and action logic, and indicate – drawing upon recent research in com...

Het voorliggende Essay is in opdracht van de Adviesraad voor het Wetenschaps- en Technologiebeleid (AWT) vervaardigd (opdracht 12 november 1999; 0523a/99/lm) door leden van het Centrum voor Filosofie van Informatie- en Communicatietechnologie (FICT) van de Erasmus Universiteit Rotterdam. Wij zijn de volgende personen dank verschuldigd voor de gener...

In 1926, Mally proposed the first formal deontic system. As Mally and others soon realized, this system had some rather strange consequences. We show that the strangeness of Mally's system is not so much due to Mally's informal deontic principles as to the fact that he formalized those principles in terms of the propositional calculus. If they are...

Without Abstract

In The emotional brain biedt de bekende hersenonderzoeker Joseph LeDoux een gemakkelijk leesbaar overzicht van wat er tegenwoordig over de neurobiologische basis van emoties bekend is. Er blijkt gedurende de laatste decennia veel vooruitgang op dit terrein te zijn geboekt. Zo heeft men gedurende lange tijd geloofd in het bestaan van het zogeheten...

We explicate the thesis of logical relativism (people of different cultures may have different logics) in logical terms. Our illustrations come from the field of paraconsistent logic.

Deontic logic is the logic of obligation, permission and prohibi- tion. Linear logic is a resource conscious logic which is well-known within computer science. Petri nets are models of concurrent dynamic processes which have been used in hundreds of applications. In this pa- per, we present a deontic linear system with Petri net semantics. This sys...

This paper supersedes the author's \An ancient Greek theory of hemispheric specialization," Clio Medica 17 (1982) 33{38. It is argued that the ancient Greek theory about functional cerebral asymmetry dis- cussed in that article can hardly have been put forward before the third century B. C. It should therefore not be attributed to Diocles of Caryst...

We describe a new way in which theories about the deontic status of actions can be represented in terms of the standard two-sorted first-order extensional predicate calculus. Some of the resulting formal theories are easy to implement in Prolog; one prototype implementation--R. M. Lee's deontic expert shell DX--is briefly described.

Using Fagin's and Halpern's local reasoning models and an epis-temic variant of Jennings's and Schotch's semantics of weakly aggregative modal logic, we argue that the hypothesis that split-brain patients have two coherent minds is preferable to the hypothesis that they have one incoher-ent mind.

This paper is a sequel to the author's 'An ancient Greek theory of hemispheric specialization', Clio Medica 17 (1982) 33-38. It is concluded that the ancient Greek theory about functional cerebral asymmetry discussed in that article can hardly have been put forward before the third century B.C. It should therefore not be attributed to Diocles of Ca...

Logique & analyse, Nouvelle s erie, 37e ann ee, No 146 (Juin 1994), pp. 129{143. Abstract We present a logical reconstruction of Aristotle's views on reectiv e awareness (De Anima III.2, 425b12{25, and De Somno 2, 455a12{22).

The paper presents a formal explication of the early Wittgenstein's views on ontology, the syntax and semantics of an ideal logical language, and the propositional attitudes. It will be shown that Wittgenstein gave a language of thought analysis of propositional attitude ascriptions, and that his ontological views imply that such ascriptions are tr...

In order to study the modal status of antinomies (provable contra- dictions), we present two modal extensions of the antinomic calculus proposed by F. G. Asenjo and J. Tamburino in their \Logic of antinomies", Notre Dame Journal of Formal Logic 16 (1975), pp. 17{44. Both systems are proved to be absolutely consistent and to be sound and complete wi...

In 1926, Ernst Mally proposed the first system of deontic logic. His system turned out to be unacceptable. How can it be repaired? We discuss several proposals to reformulate it in terms of strict implica-tion, relevant implication and strict relevant implication.

How should our logic express what other logics deem necessary? How should we give a rational account of forms of rationality which are dier- ent from ours? The present paper answers these questions. It shows how to enrich logical systems with operators which describe what is necessary, rational and imaginary according to other systems. Although onl...

1995 G. J. C. Lokhorst. De oudste theorie over hemisfeerspecialisatie. Ge-WiNa: Tijdschrift voor de geschiedenis der geneeskunde, natuur-wetenschappen, wiskunde en techniek, 18 (3): 37–50, 1995. ISSN 0928–303X. Superseded by hemispheres. 1 Hemisfeerspecialisatie 'De hersenen van de mens zijn dubbel, net zoals die van alle andere dieren.' Zo begint...