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Here is the dilemma. Either arguments containing imperatives can be valid or not. On the one hand, if such arguments can be valid, we need a new or expanded account of logical validity and the concomitant details. Providing such an account has proved challenging. On the other hand, if such arguments
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held that no declarative conclusion can be validly drawn from a set of premises which cannot validly be drawn from the declaratives among them alone. There is no consensus among logicians about the truth or falsity of these (or similar) claims and mixed imperative and declarative inference remains
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be fulfilled in an acceptable possible world; The conclusion "It is obligatory to clean your room or burn the house down" does not falsify the premise "It is obligatory to clean your room". In addition, based on the context, it may also be true that "It is obligatory to not burn the house down", in
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However, an argument is valid if the conclusion follows from the premises. This means the premises give us reason to believe the conclusion, or, alternatively, the truth of the premises determines truth of the conclusion. Since imperatives are neither true nor false and since they are not proper
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highlights the challenge faced by anyone who wants to modify or add to the standard account of validity. The challenge is what we mean by a valid imperative inference. For valid declarative inference, the premises give you a reason to believe the conclusion. One might think that for imperative
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cannot be valid (either because such arguments are all invalid or because validity is not a notion that applies to imperatives), then our logical intuitions regarding the above argument (and others similar to it) are mistaken. Since either answer seems problematic, this has come to be known as
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to an argument with imperatives such that a truth-value can be assigned to the proposition. For example, it may be hard to assign a truth-value to the argument "Take all the books off the table!", but
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under the scope of an imperative operator leads to unintuitive (or apparently absurd) results. When applied to simple declaratives, the result appears to be valid deduction.
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Aside from intrinsic interest, imperative logic has other applications. The use of imperatives in moral theory should make imperative inference an important subject for
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inference, the premises give you a reason to do as the conclusion says; While Ross's paradox seems to suggest otherwise, its severity has been subject of much debate.
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252:("take all the books off the table"), which means "It is obligatory to take all the books off the table", can be assigned a truth-value, because it is in the
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Frege, G. (1892) 'On sense and reference', in Geach and Black (eds.) Translations from the
Philosophical Writings of Gottlob Frege Oxford: Blackwell.
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or more generally what role truth and falsity play in their semantics. Thus, there is almost no consensus on any aspect of imperative logic.
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In this case, all the sentences making up the argument are imperatives. Not all imperative inferences are of this kind. Consider again:
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held that no imperative conclusion can be validly drawn from a set of premises which does not contain at least one imperative. While
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which case any acceptable possible world must have "Your room is cleaned" and "The house is not burnt down" to be both true.
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objects of belief, none of the standard accounts of logical validity apply to arguments containing imperatives.
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Notice that this argument is composed of both imperatives and declaratives and has an imperative conclusion.
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Hare, Richard M. (1967). Some alleged differences between imperatives and indicatives.
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However, a similar inference does not seem to be valid for imperatives. Consider:
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565:(2nd ed.). Taylor & Francis. Chapter 12: Deontic and Imperative Logic.
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Mixed inferences are of special interest to logicians. For instance,
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Poincaré, Henri (1913). Dernières Pensées. Paris: Ernest
Flammarion.
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160:. It seems that arguments with imperatives can be valid. Consider:
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P1. Do both of the following: wash the dishes and clean your room!
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The following is an example of a pure imperative inference:
206:, it received a more developed formulation by Jørgensen.
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C1. Therefore, clean your room or burn the house down!
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557:, Entry for The International Encyclopedia of Ethics
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While this problem was first noted in a footnote by
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C1. Therefore, the room is clean or grass is green.
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451:Jørgensen, J. (1938) 'Imperatives and logic',
212:takes the approach of adding a modal operator
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267:observed that applying the classical rule of
144:, it is not clear whether imperatives denote
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312:Some strands of this debate connect it to
488:Ross, A. (1944) ‘Imperatives and Logic’,
466:Ross, A. (1941) ‘Imperatives and Logic’,
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117:Learn how and when to remove this message
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156:One of a logic's principal concerns is
53:Please improve this article by adding
343:P1. Take all the books off the table!
304:requires that all obligations in the
164:P1. Take all the books off the table!
7:
939:What the Tortoise Said to Achilles
478:10.1111/j.1755-2567.1941.tb00034.x
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335:C1. Therefore, clean your room!
577:Covers mostly the approach of
1:
55:secondary or tertiary sources
553:Peter B. M. Vranas (2010),
302:semantics for Deontic logic
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1277:
561:Harry J. Gensler (2010).
409:List of Logical Paradoxes
355:Foundations of Arithmetic
348:Foundations of Arithmetic
176:Foundations of Arithmetic
169:Foundations of Arithmetic
595:, University of Virginia
269:disjunction introduction
858:Paradoxes of set theory
533:Charles Leonard Hamblin
259:
151:
555:IMPERATIVES, LOGIC OF*
318:paradox of free choice
275:P1. The room is clean.
246:
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42:relies excessively on
579:Héctor-Neri Castañeda
563:Introduction to Logic
491:Philosophy of Science
404:Free choice inference
247:
227:
1224:Kavka's toxin puzzle
996:Income and fertility
353:C1. Therefore, take
286:P1. Clean your room!
236:
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174:C1. Therefore, take
883:Temperature paradox
806:Free choice paradox
670:Fitch's knowability
591:Mitchell S. Green,
539:. Basil Blackwell.
306:domain of discourse
189:Jørgensen's dilemma
152:Jørgensen's dilemma
1259:Prisoner's dilemma
945:Heat death paradox
933:Unexpected hanging
898:Chicken or the egg
242:
222:
66:"Imperative logic"
18:Ross' paradox
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1304:
976:Arrow information
572:978-0-415-99650-1
546:978-0-631-15193-7
245:{\displaystyle O}
225:{\displaystyle O}
140:. In contrast to
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16:(Redirected from
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1096:Service recovery
950:Olbers's paradox
650:Buridan's bridge
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593:Imperative Logic
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350:is on the table.
324:Mixed inferences
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193:Jørgen Jørgensen
171:is on the table.
158:logical validity
132:is the field of
130:Imperative logic
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68: –
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62:Find sources:
56:
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40:This article
38:
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29:
28:
19:
1249:Preparedness
1081:Productivity
1061:Mandeville's
853:Opposite Day
781:Burali-Forti
776:Bhartrhari's
562:
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377:Applications
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146:propositions
142:declaratives
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107:October 2012
104:
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41:
1179:Condorcet's
1031:Giffen good
991:Competition
745:White horse
720:Omnipotence
537:Imperatives
414:Speech acts
138:imperatives
1254:Prevention
1244:Parrondo's
1234:Navigation
1219:Inventor's
1214:Hedgehog's
1174:Chainstore
1157:Population
1152:New states
1086:Prosperity
1066:Mayfield's
908:Entailment
888:Barbershop
801:Epimenides
494:11: 30–46.
472:7: 53–71.
457:7: 288-98.
454:Erkenntnis
430:References
419:Pragmatics
387:metaethics
77:newspapers
44:references
1269:Willpower
1264:Tolerance
1239:Newcomb's
1204:Fredkin's
1091:Scitovsky
1011:Edgeworth
1006:Easterlin
971:Antitrust
868:Russell's
863:Richard's
836:Pinocchio
791:Crocodile
710:Newcomb's
680:Goodman's
675:Free will
660:Epicurean
631:paradoxes
370:R.M. Hare
314:Hans Kamp
1312:Category
1297:Category
1194:Ellsberg
1046:Leontief
1026:Gibson's
1021:European
1016:Ellsberg
986:Braess's
981:Bertrand
959:Economic
893:Catch-22
873:Socratic
715:Nihilism
685:Hedonism
645:Analysis
629:Notable
535:(1987).
393:See also
265:Alf Ross
1199:Fenno's
1164:Arrow's
1147:Alabama
1137:Abilene
1116:Tullock
1071:Metzler
913:Lottery
903:Drinker
846:Yablo's
841:Quine's
796:Curry's
759:Logical
735:Sorites
725:Preface
705:Moore's
690:Liberal
665:Fiction
469:Theoria
373:vexed.
91:scholar
1106:Thrift
1076:Plenty
1051:Lerner
1041:Jevons
1036:Icarus
966:Allais
928:Ross's
766:Barber
750:Zeno's
695:Meno's
569:
543:
383:ethics
93:
86:
79:
72:
64:
1209:Green
1189:Downs
1121:Value
1056:Lucas
923:Raven
831:No-no
786:Court
771:Berry
204:Frege
134:logic
98:JSTOR
84:books
1287:List
1111:Toil
826:Card
821:Liar
567:ISBN
541:ISBN
515:Mind
385:and
346:P2.
300:The
167:P2.
70:news
474:doi
316:'s
199:).
46:to
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197:da
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