Fabrizio Macagno. Informal Logic, Vol. 31, No. 4 (2011), pp. 368-394. The Presumptions of Meaning: Hamblin and Equivocation FABRIZIO MACAGNO ArgLab Instituto de Filosofia da Linguagem (IFL) Universidade Nova de Lisboa Edifício I&D 4 andar Avenida de Berna 26, 1069-061 Lisboa, Portugal fabrizio.macagno@fcsh.unl.pt Abstract: The force and the deceptive nature of the fallacy of equivocation lies in its dialectical nature. The speaker redefines a word in order to classify a fragment of reality, while the hearer draws a conclusion based on the ordinary meaning of such a classification. This difference between the interlocutors' meanings is grounded on a crucial epistemic gap: how is it possible to know our hearer's mind, and his knowledge of the words we used? Building on Hamblin's account of equivocation, the speaker's meaning and the manipulative strategies based on redefinitions can be explained as the conclusion of an implicit reasoning based on a presumption of ordinary meaning. Résumé: La force et le caractère trompeur du sophisme d'équivocation réside dans sa nature dialectique. L'orateur redéfinit un mot pour classer un fragment de la réalité, tandis que l'auditeur tire une conclusion fondée sur le sens ordinaire d'une telle classification. Cette différence entre les significations des interlocuteurs est fondée sur un écart épistémique crucial: comment est-il possible de connaître l'esprit de notre auditeur, et sa connaissance des mots que nous avons utilisés? S'appuyant sur la description de Hamblin de l'équivocation, la signification du locuteur et les stratégies de manipulation basées sur les redéfinitions peuvent être considérées comme la conclusion d'un raisonnement implicite fondé sur une présomption de signification ordinaire. Keywords: interpretation, dialectical strategies, persuasion, argumentation schemes, burden of proof, equivocation, Hamblin, presumption, redefinition. 1. Introduction Hamblin's approach to equivocation is based on a crucial principle: equivocation is a dialectical problem that needs to be Hamblin and Equivocation 369 solved as a procedural point (point of order) and not as a substantial, or topical, point (Hamblin, 1970: 284). On Hamblin's view, equivocation, like all properties of linguistic entities, is dependent on the rules of the dialogue (1970: 285), on procedures that somehow can go wrong. On this account, problems related to word meaning are solved dialectically because meaning is tackled from a dialogical perspective, as a dialectical property (Hamblin, 1970: 285). Hamblin maintains that meaning cannot be described an abstract state of mind, independently from a dialogical context. On the contrary, he claims that meaning needs to be accounted for as a property determinable from the pattern of use of a linguistic entity. For him, what makes a linguistic entity to have the same meaning in different contexts, or in the same dialogue or sentence, is a convention. Therefore, problems arising from equivocation need to be solved at a procedural level, that is, at the level of the dialogical rules that need to be agreed upon in a specific context of dialogue (Mackenzie, 2007: 225). On Hamblin's theory of dialectical meaning, meaningfulness, nonsense and equivocation are interpreted in terms of dialogical behavior (Hamblin, 1970: 286). However, the analysis of Fallacies is especially focused on the breaches to the rules of dialogue, or the conventions governing the use of words. In this work the linguistic behavior that shall be complied with, or that can be voluntarily or involuntarily infringed, is not described, and the mischievous strategies grounded on the use of equivocation are not approached. If we shift our attention from the representations of arguments to real cases, we notice that there is a fundamental difference between the analysis of equivocation and its use. In political discourses or in law it is possible to find cases in which words are used with a specific meaning by the speaker, and interpreted differently by the hearer. This mechanism, or mistake, can become a dangerous (or effective) dialectical strategy when it is created on purpose, or when ambiguity is not even expected by the hearer (van Laar, 2003). In such cases, concepts usually regarded as having a shared meaning can be implicitly redefined. The real problem with equivocation is not when homonymic or polisemic words such as "bank," "duck" or "location" are used first to refer to a concept (a building, a bird, a position) and then to a different one (a (river verge, a movement or the opposite of a drake, an action of placing something) (Hamblin, 1970: 287). Equivocation becomes a real move in a dialogue when words are used by the speaker with a specific meaning, different from the usual one, and the hearer accepts and interprets such a move based on what their commonly shared meaning refers to. A famous contemporary case of (unsuccessful) Fabrizio Macagno 370 equivocation is Obama's use of the term "hostility." He claimed that US military operations in Libya did not need any Congress authorization, as they were not "hostilities." The interlocutor, the Congress in this case, could accept the conclusion (no need for authorization) as following from the premises (no hostilities) only if the word had the meaning of "any act of warfare." However, how can bombings be excluded from acts of warfare? Obama used this term with a meaning different from the usual one, implicitly redefining it as an "intervention exclusively involving ground troop intervention, sustained fighting and exchanges of fire" (Obama Administration letter to Congress justifying Libya engagement, June 15th, 2011, p. 25). Obama's unvoiced account of hostility, however, could not be accepted by the Congress and the military1. On this perspective, equivocation is really dangerous not when the problem of meaning constancy can arise, but when it should not be even considered. For instance, essentially contested concepts (see Gallie, 1956; Reitan, 2001), such as "peace" or "democracy," can be used by the speaker with a definition that is potentially different from the one the hearer uses to interpret their meaning. However, when the hearer is not even aware that a word can have different meanings, the risk of not detecting such a move is much higher. From a dialogical point of view, equivocation cannot be simply regarded as misunderstanding or error. On the contrary, it is a strategy in which misunderstanding is created and used to achieve a dialogical goal. The purpose of this paper is to develop Hamblin's theory of dialectical meaning to describe the dialogical effects of the use of a word, and investigate the dialogical uses of equivocation as a mischievous move and as a dialectical attack. Hamblin's account of meaning highlights a fundamental epistemic problem, consisting in the gap between the speaker's use of a word and the hearer's knowledge of its meaning. How can a speaker know the other's mind? How can the hearer know the speaker's intended meaning, eventually disambiguated by the context and co-text? Hamblin inquired into this type of knowledge using the concept of presumption, defined as reasoning in the absence of evidence, grounded on usual expectations and ordinary course of events. This concept can be used to explain an important dialectical dimension of the use of a word. 1 C. Savage, 2 Top Lawyers Lost to Obama in Libya War Policy Debate. The New York Times June 17, 2011 (Retrieved from http://www.nytimes.com/2011/06/18/world/africa/18powers.html?_r=1 accessed on October 21st, 2011). Hamblin and Equivocation 371 2. A dialectical theory of meaning On Hamblin's view, meaning is dialectical in the sense that it is a pattern of verbal behavior relative to a group of language users (Hamblin, 1970: 290-291). He maintains that this perspective is consistent with Quine's and Grice and Strawson's analysis of meaning as behavioral reaction to a statement. Quine's attack on the distinction analytic-synthetic led him to replace the notion of analytic statements with the concept of degree of belief corrigibility (Quine, 1951). Hamblin contends that this approach can be conceived as dialectical, as synonymy, and therefore meaning, is explained in terms of corrigibility of knowledge. The more such knowledge is shared within a group, and is therefore connected to a cognitive system (the system of one's beliefs), the less it can be corrected without reorganizing the whole conceptual structure (Hamblin, 1970: 291). Grice and Strawson (1958) interpreted the concept of shared corrigibility in terms of possible denials. On this view, the denial of analytic statements leads to incomprehensibility, because it amounts to the denial of the attribution of certain "essential" definitional properties to a predicate used to refer to an entity. For instance, they maintain that the statement "My neighbor's three-year-old child is an adult" is meaningless, as it cannot be understood by the interlocutor (Grice & Strawson, 1958: 150-151). In this case, an essential property of "being adult" is contradicted by the predicate "being three-years old." In these two approaches the problem of analyticity and meaning is interpreted in a pragmatic, and therefore dialectical, perspective. On Hamblin's view, belief-change and understandability, or corrigibility, are thought of as pragmatic concepts. According to this perspective, they amount to the hearer's intention or willingness to modify a conceptual structure, or to his possibility of understanding a statement. As Hamblin put it, Meanings of words are, of course, always relative to a language-user or a group G of language-users. The meanings any group G attaches to words are determinate in terms of the (zero-order) statements that are relatively incorrigible or analytic to G. (Hamblin, 1970: 291) Hamblin, however, notices how these accounts of meaning rest on the assumption that the language behavior of a group or a person is systematic and coherent. For this reason, in order to investigate equivocation he formulates the concepts of truth, falsity, and synonymy in dialectical terms, grounding them on the inter-subjective concepts of agreement or disagreement: Fabrizio Macagno 372 If there is a dialectical theory of truth it must run something as follows: 'It is true that S' means (very nearly) the same as 'S', and 'That is true', 'That is false' are phrases used in dialogues to indicate agreement and disagreement. (Hamblin, 1970: 293-294) Truth and falsity, synonymy and non-identity of meaning are in this account dialectical issues, concerning whether the interlocutor agrees or disagrees with a viewpoint (Hamblin, 1970: 243). This definitional change or dialectical interpretation of the concept of meaning and synonymy opens up a crucial problem: how is a dialogue possible, if potentially every word needs to be agreed upon by every interlocutor? Why do we usually consider equivocation and misunderstanding as exceptions, and not as the rule? How can we know that the interlocutor will agree with us, or understand us, and why do not we define every word we use? In order to address these problems, Hamblin advances a new idea of meaning. He claims that what makes equivocation an exception, and dialogues possible, is the notion of presumption. On this view, we ground our discourse on presumptions, such as the speaker uses his words in compliance with their common use, the meaning of a word is the pattern of its use, or the meaning of a word used more than once in the same argument or discourse is the same. These presumptions are forms of reasoning in absence of evidence to the contrary. Since we cannot know whether our interlocutor agrees or disagrees with our use of certain words, or whether he interprets the same words as having the same meaning or a different one, we act on the basis of common experience, on what usually happens. As Hamblin put it: There is, as we might put it, a presumption of meaningconstancy in the absence of evidence to the contrary. The presumption is a methodological one of the same character as the legal presumption that an accused man is innocent in the absence of proof of guilt, or that a witness is telling the truth: it is not, of course, itself in the category of a reason or argument supporting the thesis of meaningconstancy, and least of all is it an argument for the impossibility of equivocation. Dialectic, however, has many presumptions of this kind, whose existence is related to the necessary conditions of meaningful or useful discourse. It is a presumption of any dialogue that its participants are sober, conscious, speak deliberately, know the language, mean what they say and tell the truth, that when they ask questions they want answers, and so on. (Hamblin, 1970: 294-295) Hamblin and Equivocation 373 Hamblin's treatment of the mutual understanding of meaning in terms of presumption carries noticeable dialectical implications. As he noticed, presumption is a methodological, and therefore dialectical, ground of reasoning. Rescher described it as a generalization used in conditions of lack of evidence, holding as true until a contrary (stronger) argument is advanced, or the contrary conclusion is proved (see Rescher, 1977: 1; 26). Presumptions, therefore, are not laws or proofs, but simply defeasible rules that are subject to default and can be used when positive evidence is missing (Rescher, 2006: 33). For instance, the use of a proper name or a definite description carries with it the presumption that in the given context it has a unique referent, and that the audience can identify it (Mackenzie, 1988: 479). These presumptions fail when the audience asks for clarification and points out that it is not possible to identify a unique referent or a referent at all. Similarly, the use of a word carries the presumption that it has been used according to its ordinary usage, which can be identified and accepted by the interlocutor. However, the hearer may agree to a different definition of the word, or challenge that the speaker's use of such a word corresponds to the ordinary one. Since presumptions are defeasible, they shift the burden of proof (Pinto, 1984; Walton, 1993; 2008) in the sense that the other party has to advance a contrary argument fulfilling a certain standard of proof that depends on the probability of the connection between the fact (C) and the conclusion (P) (Best et al., 1875: 571). According to Hamblin, this mechanism of presumption governs ordinary misunderstanding and equivocation. The interlocutor, claiming or assuming that there is an equivocation or that a word is used contrary to its common usage, has to prove or advance reasons to support his claim (Hamblin, 1970: 294). In some cases, we can notice, evidence to the contrary is simply provided by the hearer's inability to find a unique referent. In other cases, he has to distinguish the different meanings and sometimes prove that such meanings correspond to ordinary use. Hamblin introduced the idea that the use of words depends on a set of presumptions about the interlocutor's knowledge and acceptance of the meaning attributed to them by the speaker. This principle can be used to explain why equivocation can be sometimes used to deceive the interlocutor, and when it simply amounts to a mistake. In order to develop Hamblin's idea in this direction, it is necessary to discuss in detail the reasoning underlying the use of a word. 3. Words and dialogical moves Fabrizio Macagno 374 Hamblin considered a specific dimension of the meaning of a word, namely its role when used in a dialogical move. What needs to be analyzed is the relationship between a dialogue move and the interlocutors. More specifically, the focus of this research concerns the conditions that need to be fulfilled in order for a move to be felicitous, i.e. adequate to bring about a dialogical effect on the interlocutor (Grice, 1989: 220; Levinson, 1983: 97), which in its turn corresponds to a possible continuation of the dialogue (Grice, 1975: 45). For example, a question can be considered as felicitous if the interlocutor continues the dialogue by answering accordingly, or refusing to answer; a statement is felicitous if the hearer replies, taking into consideration the subject matter or the information provided. In dialectical terms (Walton, 2010: 14; Walton, 1989: 65-71), dialogical moves open up possible continuations of dialogue and exclude others. For instance, we can consider the following dialogue: "You should learn not to make personal remarks," Alice said with some severity; "it's very rude." The Hatter opened his eyes very wide on hearing this; but all he said was, "Why is a raven like a writing-desk?" (Carroll, 2010: 44) Here, the dialogue as a whole can be hardly considered to be felicitous. Alice's move was completely void in a world governed by different dialogical rules. Her remark could not affect in any way the Hatter's continuation of the dialogue. This relationship between a move and the constraints it imposes on possible future moves can be represented as a predicate connecting dialogue sequences with their context and the interlocutors. In linguistics it has often been referred to as a "rhetorical predicate" (Grimes, 1975: 209ff), later named a "logical-semantic connective" (Crothers, 1979, Rigotti, 2005) or a "coherence relation" (Hobbs, 1979: 68; Hobbs, 1985). Examples of these relations can be explanation, alternative, support, etc. (Asher & Lascarides, 2006). These abstract predicates impose a set of requirements conditions, or pragmatic presuppositions (Stalnaker, 1974; Vanderveken, 2002: 47; Bach, 2003: 163) both on the asserted move and the possible future replies. For instance, the statement "Bob went to the theatre yesterday" pragmatically presupposes that the hearer can identify who Bob is, that he is interested in Bob, that he can understand what a theatre is and what "going to the theatre" means and implies. Moreover, the hearer is bound to reply considering the statement. For instance he can continue the dialogue by commenting on it, asking questions, etc. A reply like the one that the Hatter gave to Alice's remark would breach the conditions of the coherence Hamblin and Equivocation 375 relation. From a pragmatic perspective, these relations can be considered as high-level speech acts (Grice, 1989: 362; Carston, 2002: 107-108) that specify the roles of the first level speech acts, or rather, their felicity conditions (Vanderveken, 2002: 28; Austin, 1962: 34; 51). We can structure the language used in terms of predicates, and conceive the relationship between a move and the possibilities that it opens as a high-level predicate (corresponding to the discourse purpose). This predicate assigns a role to each dialogical act (Grosz & Sidnert, 1986: 178; Walton, 1989: 68) and imposes specific requirements on the relation between the hearer and the speaker's move. One of the most crucial coherence conditions is the hearer's understanding of the speaker's move. This requirement emerges especially when the hearer cannot continue the dialogue because the speaker's intended effect cannot be even accommodated (Lewis, 1979), reconstructed or anyhow retrieved. In these cases, the very purpose of the move seems to be completely obscure, and the hearer needs to interrupt the dialogue and ask for clarification, or reject the move as unclear or nonsensical (Walton, 2007: 170). For instance, let's consider the famous Humpty Dumpty example (emphasis added): "[...] there are three hundred and sixty-four days when you might get un-birthday presents-and only one for birthday presents, you know. There's glory for you!" "I don't know what you mean by 'glory'," Alice said. Humpty Dumpty smiled contemptuously. "Of course you don't-till I tell you. I meant 'there's a nice knockdown argument for you!'" "But 'glory' doesn't mean 'a nice knock-down argument'," Alice objected. "When I use a word," Humpty Dumpty said, in rather a scornful tone, "it means just what I choose it to mean- neither more nor less." "The question is," said Alice, "whether you can make words mean so many different things." "The question is," said Humpty Dumpty, "which is to be master-that's all." Alice was too much puzzled to say anything; so after a minute Humpty Dumpty began again. "They've a temper, some of them-particularly verbs: they're the proudest- adjectives you can do anything with, but not verbs- however, I can manage the whole lot of them! Impenetrability! That's what I say." "Would you tell me, please," said Alice, "what that means?" Fabrizio Macagno 376 "Now you talk like a reasonable child," said Humpty Dumpty, looking very much pleased. "I meant by 'impenetrability' that we've had enough of that subject, and it would be just as well if you'd mention what you mean to do next, as I suppose you don't mean to stop here all the rest of your life." (Carroll, 2010: 57) In this dialogue, Humpty Dumpty performs infelicitous, or rather void, moves (Austin, 1962: 35-36). Alice could not understand the purpose of his interlocutor's uttering "There's glory for you!" or "Impenetrability!" She could not continue the dialogue, as she could not even imagine for what purpose her interlocutor performed his moves (Rigotti & Rocci, 2001). The relationship between the speaker's intention and the hearer's recognition of the possible replies allowed by the move is breached. We can represent the dialogical interpretation of meaning and its breach as follows: Figure 1: Dialectical interpretation and dialogical effects Humpty Dumpty, using words that cannot be possibly understood by Alice, is breaching a fundamental requirement for a dialogue move to bring about its intended dialogical effect. He deliberately fails to use words that can be possibly known by the hearer, and that the hearer can possibly connect with her background knowledge (Asher & Lascarides, 1998: 255; Searle, 1981: 135). Carroll's fantastic and irrational character is simply using words that cannot change Alice's dialogical situation by inserting new commitments or opening possible moves she can perform as a reply2. Alice is left with no clues on how to con- 2 Obviously this treatment of nonsense is strictly dialogical, limited to the direct effects of a move, without considering its (desired or involuntary) side effects. Humpty Dumpty may have talked nonsense in order to puzzle Alice, or show his superiority. Friends can use words with new invented meanings Hamblin and Equivocation 377 tinue the dialogue, except for the possibility of interrupting the conversation itself to meta-dialogically inquire about the meaning of the words used and the purpose of the discourse segment (Ginzburg, 1998). As we notice from the case above, dialogue is based on a crucial epistemic gap. It is grounded on the requirement that the speaker uses words with a meaning shared by the hearer and connected with facts and entities that are part of the interlocutors' background knowledge. But how can the speaker know what the hearer knows or holds as background knowledge? How is it possible to know that the hearer can identify a unique meaning or referent for the words used? This philosophical problem can be tackled from a legal perspective, as this epistemic impossibility is mirrored on a crucial legal issue, legal interpretation. The most basic legal principle is that people are presumed to know the laws, and, more specifically, what the laws exactly mean. However, although on the one hand specific terms are explicitly defined in the statute, on the other hand it is not possible to define all the words used. How is it possible to presume that people know the exact meaning of a law, if only some words are defined? In law, this deadlock is solved through the application of two rules: 1) words, when they are not technical terms and have not been previously defined, shall be interpreted according to their ordinary meaning, determined on the basis of a dictionary (City of Spokane ex rel. Wastewater Mgmt. Dep't v. Dep't of. Revenue, 145 Wn.2d 445, 454, 2002); and 2) a person should not be held responsible for violating a law that could be interpreted in a number of ways. In such an event, the interpretation most favorable to the defendant shall apply (Tromble, 1999: 543). In law, therefore, the individuals are not simply presumed to know the law, but also the ordinary meaning of the words used (McDermott Int'l, Inc. v. Wilander, 498 U.S. 337, 342, 1991). The interlocutor's knowledge of the meaning of the words can be conceived as the conclusion of a presumptive reasoning that can be described as follows (Rescher, 2006: 33): Presumptive reasoning Premise 1: P (the proposition representing the presumption) obtains whenever the condition C obtains unless in a conversation in order to amuse themselves. However, this second indirect (or interactional, or meta-dialogical) sense depends on a first-level direct (or dialogical) nonsense, which is the subject matter of this paper. In the examples above, the impossibility of understanding the meaning may produce an indirect interactional effect because it prevents the interlocutor from dialogically engaging in the conversation. Fabrizio Macagno 378 and until the standard default proviso D (to the effect that countervailing evidence is at hand) obtains. (Rule) Premise 2: Condition C obtains. (Fact) Premise 3: Proviso D does not obtain. (Exception) Conclusion: P obtains. This pattern of reasoning can be used to describe presumptive meaning. The rule of presumption is that "people know the ordinary meaning of the words used." Therefore, if a specific meaning (M) is commonly associated with a word (W), people are presumed to know that W means M. The ordinary meaning is established by experience, and, should conflicts arise, by appeal to authorities or popular opinion. In law, dictionaries are presumed to report people's common understanding of a word. In the event of a conflict of opinion between equally acknowledged dictionaries, the ordinary meaning is presumed to be reflected in journalists' use of such a word (Muscarello v. United States, 524 U.S. 125, 1998). This presumptive reasoning is twofold. On the one hand, the speaker presumes the hearer's knowledge of the ordinary use. On the other hand, the hearer presumes that the speaker is complying with the common use of words. This mirror mechanism of presumptive reasoning can be represented as follows: Figure 2: Presumptions underlying the use of a word In this case, Humpty Dumpty's reasoning is represented considering Alice's conversational presumptions. From this perspective, Humpty Dumpty grounds his dialogical move on an unreasonable presumptive conclusion, based on the premise "'Impenetrability' does not ordinarily mean 'I want to change topic'" that he acknowledges to be true. By performing the move with the specific intended effect, at the same time he presumes that Hamblin and Equivocation 379 the intended meaning corresponds to the ordinary one, and he acknowledges that the intended and the ordinary meaning cannot be the same. Humpty Dumpty would be commonly considered to be unreasonable in a reasonable world. However, in a reality governed by different rules of reasonableness, the unreasonable speaker was actually Alice. In Alice's and our world, however, this type of unreasonableness often passes undetected and can lead to possible manipulations. 4. Dialectical equivocation and conflicts of presumptions Humpty Dumpty, even though confined in a world mirrored on a looking glass and governed by inverted rules, shows an important dimension of equivocation: the conflict of presumptions. As Hamblin noticed, words do not have an immutable, fixed meaning, but instead their meaning is the result of an abstraction from the patterns of their use. For this reason, they can be used to represent different concepts. A new meaning can be introduced by the speaker, or he can use the word considering a peculiar and not widely known pattern of use (Hamblin, 1970: 295). The boundaries of the freedom of word uses lie in the presumptions on which the dialogue is grounded. The first crucial presumption is the aforementioned one of ordinary use of language. In order to be able to communicate his dialogical intention, the speaker presumes that the hearer knows the ordinary meaning of the words. In order to interpret the move, the hearer presumes that the speaker is using the words according to their ordinary meaning. These two complementary presumptions set the possible limits to the freedom of stipulation, or rather the freedom of using words with a meaning that is not commonly understood (Hamblin, 1970: 300). Humpty Dumpty's move is commonly considered to be a mistake of reasoning, based on a conflict between the rule of presumption and the speaker's knowledge. The speaker presumes that a word is used according to its ordinary meaning, but at the same time he knows that its intended meaning cannot correspond to the ordinary use, for he has freely stipulated a new definition without informing his interlocutor. This case clearly amounts to unreasonableness, because the stipulated meaning cannot be confused with the ordinary one, nor can the move be differently interpreted. Sometimes, however, words can be implicitly redefined in order to take advantage of the hearer's presumptive reasoning. On the one hand, the speaker uses a word with a new meaning in order to classify a fragment of reality, but he does not make his redefinition explicit. In this fashion he presumes that it has been used in compliance with the common use. On the other Fabrizio Macagno 380 hand, the hearer is not warned of the non-ordinary meaning, and presumes that the speaker is using the word according to its commonly shared meaning. In this fashion, the speaker creates a dialogical equivocation, where the asserted statement does not correspond to the interpreted one. But for what purpose is this equivocation created? A possible answer can be found in the analysis of the argumentative force of words. The argumentative force of a word corresponds to two combined patterns of argument: an argument from classification and a further move grounded thereon, usually proceeding from an argument from values (Macagno & Walton, 2010). A word becomes argumentatively and dialogically relevant when it is used to achieve a specific purpose. For this reason, argumentative words can be described as complex processes of reasoning. They are the result of an argument from classification based on the shared definitions or rules of use, which become the premises of further arguments that can proceed from values, or consequences, or practical reasoning, etc. The argument from classification consists in the attribution of a property G in virtue of a property F, which represents its definition or one of its possible definitional criteria. In other words, if x has the property F, x has property G as well (Walton, 2006: 129; Macagno & Walton, 2009). For instance, waging war against Iraq can be considered as an act of peace if we maintain that peace is "the maintenance or promotion of social equilibrium" and that social equilibrium needs to be promoted in Iraq. The other dimension of a classification is its argumentative or dialogical effect. For instance, declaring war against Iraq an act of peace triggers an argument from values, described as follows (Walton, Reed & Macagno, 2008: 321): Argument from values PREMISE 1: Value V is positive as judged by agent A. (judgment value). PREMISE 2: The fact that value V is positive affects the argumentation and therefore the evaluation of goal G of agent A. (If value V is good, it supports commitment to goal G). CONCLUSION: V is a reason for retaining commitment to goal G. For instance peace, understood as absence of violent conflict, is commonly positively evaluated. Therefore the military intervention in Iraq, aimed at defending peace, should be considered as positive and supported. Other types of conclusions can be triggered by different classifications, leading to a different reasoning from values. For example, legal values trigger judgments Hamblin and Equivocation 381 resulting in punishment. In other cases the classification of a situation can elicit a practical reasoning (environmental problems are matter of security; therefore the department of foreign affairs should deal with them) or argument from consequences (if withdrawing the troops caused social and political instability, the withdrawal of the troops needs to be delayed). The charge of equivocation lies in the relationship between the two combined argumentative moves, which can be attributed to the same speaker or are triggered by different interlocutors (for the concept of polyphony, see Ducrot, 1980). In order to explain this mechanism, we can consider the way "eugenics" was redefined before the Second World War. At that time, its shared meaning corresponded to the "strengthening a biological group on the basis of ostensible hereditary worth" (Lifton, 1986: 24), and was commonly associated with birth campaigns. However, later on the allegedly growing number of Jews or the existence of unhealthy individuals was depicted as a problem of race, and the term "negative eugenics" was introduced to indicate a program never publicly defined (Lifton, 1986: 42). This program was approved and did not have to face any protests against or attacks on its moral or human implications. The acceptance, or rather the underestimation of the gravity of this program lay in the dialogical equivocation on which it was founded. The definition of "negative eugenics" consisted in the "sterilization of unhealthy individuals or racially inferior people and sometimes euthanasia" (Lifton, 1986: 42), where "euthanasia" was again implicitly redefined to include the killing of unhealthy people, Jewish children and other people considered as "racially inferior." The moral problem of killing German citizens, (already undermined by the advertisement campaigns that were denouncing the risk and the costs of a growing number of "lives unworthy of life") was avoided by appealing to a word with two meanings, one for the speaker, and one for the audience. The German citizens interpreted the messages according to the ordinary meaning of the words "eugenics," "lives unworthy of life" or "euthanasia." They positively judged a program whose purpose was to select the best race and avoid social problems or costs through controlling births or relieving the incurable sick from unbearable suffering (according to the ordinary meaning of "euthanasia"). The speaker presumed such an interpretation, but used the same words to refer to the killing of healthy German people. The speaker presumed that the words were not the ordinary ones, but at the same time they were left undefined, so that they carried the presumption for the hearer that they meant their commonly shared meaning. Humpty Dumpty was unreasonable because he presumed that Alice could not understand his message. The promoters of the racial Fabrizio Macagno 382 campaign, on the contrary, presumed that the audience could retrieve a communicative intention and provide a reply, which could not correspond to what the speaker was referring to. This dialogical equivocation can be represented in Figure 3. Figure 3: Dialogical equivocation and conflicts of presumptions This example is an extreme instance of the use of dialogical equivocation to hide reality. From this case it is possible to notice how the speaker can take advantage of the hearer's presumptive reasoning in order to communicate a different reality, so that a different interpretation and value judgment can be triggered. This strategy can be also used in political discourse to alter the interlocutor's perception and judgment of an already shared fragment of reality. For instance, we can consider the following excerpt from President Obama's Nobel Price Acceptance Address3 (emphasis added): Peace is not merely the absence of visible conflict. Only a just peace based on the inherent rights and dignity of every individual can truly be lasting. Peace is unstable where citizens are denied the right to speak freely or worship as they please; choose their own leaders or assemble without fear. A just peace includes not only civil and political rights-it must encompass economic security and opportunity. For true peace is not just freedom from fear, but freedom from want. 3 Barack Obama, Nobel Peace Prize Acceptance Address Oslo, Norway December 10, 2009. Retrieved from www.nytimes.com/2009/12/11/world/europe/11prexy.text.html, accessed on October 10th, 2011). Hamblin and Equivocation 383 This argument was aimed at justifying the acceptance of a peace award granted to a president who waged two wars. The force of the whole reasoning lies on the commonly accepted evaluation of peace, and on a redefinition of this concept. Obama built his speech relying on a simple reasoning from values, which can be described as follows: 1) people usually desire what is good, and 2) peace is good; 3) what leads to the good is usually considered as good, and therefore 4) what leads to peace is usually considered as good (Aristotle, Rhetoric 1363b 13-16; Vendler, 1964). However, he had to challenge the common opinion that war is not peace, and that waging war (or rather breaking peace) in order to obtain peace is not commonly understood as good. Therefore, Obama's strategy was based on an implicit and explicit redefinition of peace. He introduced a new species of peace, "just peace," and defined it as "freedom from fear and want." However, this definition hides an implicit redefinition on which the whole strength of the argument depends: the meaning of the general idea "peace" encompassing just and unjust peace. The new concept of "just peace" cannot be considered as a species of "absence of violent conflicts or civil disorders." In fact, this latter shared definition of peace is contrary to the concept of war. "Just peace" can be considered as a form of peace only redefining this latter in a way admitting for the possibility of waging war, namely as a "condition of social equilibrium." This new meaning creates a dialogical equivocation. Obama supported his decisions claiming that his decisions were aimed at using military force to impose a condition of just social equilibrium in other countries. However, what people usually regard as praiseworthy is a policy directed towards the absence of violent conflict. The two definitions are used for two different dialogical goals. The redefinition supports an argument from classification, while the old definition is used to trigger reasoning from values. In this fashion, the new meaning prevents inconsistency, but at the same time the old meaning supports a positive value judgment. The dialectical equivocation can be represented as follows: Avoiding contradiction Triggering positive value judgment I declared war to defend just peace. I declared war to defend just peace. Peace is a condition of just social equilibrium. Peace is a condition of absence of conflict. I declared war to bring about a condition of just social equilibrium in other countries. Reasoning from Classification I declared war to avoid conflicts. (contradiction) Fabrizio Macagno 384 Declaring war to influence other nations' social conditions is not good. Avoiding conflicts is good. Obama's policy is not good. Reasoning from Values Obama's policy is good. Obama exploits the presumed ordinary meaning and at the same time the new meaning. From a logical point of view, he presumes that people consider his argument based on the new implicit definition. From a strategic point of view, he presumes that people assess his decisions based on their values associated with the old concept of peace. The strategy of dialectical equivocation is particularly evident when a new meaning is created and introduced for the purpose of taking advantage of the interlocutor's difference in interpreting the dialogical move. The most evident case is the aforementioned example the implicit redefinition of hostility (see section 1, above). Here Obama presumes that the hearer knows a definition clearly conflicting with the commonly accepted one, in order to lead his audience to accept that bombings are "non-hostile acts." The presumption of ordinary use of the word can be also used strategically or manipulatively with contested or vague concepts. The words expressing them may have different meanings, or an unclear one, even though one of them is preferential, or some of its features are prototypical. The preferential or prototypical meaning is the one that prevails over the other meanings or traits in conditions of lack of contrary evidence. For instance, "security," when used in political contexts and restricted to the "security of a nation," is commonly associated with protection against military threats. However, this word has been extensively redefined to indicate a protection against generic and possible dangers (Broda-Bahm, 1999; Garcia, 2010; Penny, 2007). The political use of the word "security" carries a dialogical ambiguity (see van Laar, 2003) between the old and commonly shared meaning (defense from external threat) and the new one, indicating environmental policies or other types of actions to be taken in protection of goods or resources depending on other states. This ambiguity can be used to trigger judgments and evaluations related to the idea of possible aggression, or underlie how global concerns reflect on national interests. 5. Presumptions and charges of equivocation: Ambiguity and distinguo Hamblin and Equivocation 385 The process of conveying a meaning and interpreting a dialogical move is grounded on several presumptions. Hamblin pointed out the constancy of meaning. A more powerful one can be described as the correspondence with the ordinary use of the word. This latter criterion embodies two crucial requirements: that the meaning is presumed to correspond to the common use, and that the use of the word in the text mirrors one meaning that is commonly shared. The text itself, or rather the use of the word, is presumed to coincide with the common expression of one communicative intention, one meaning. Obviously, this is only a presumption, which represents one of the forms of reasoning underlying the interpretation of a text. The failure of such an expectation results in presumptive infelicity or communicative failure. Implicatures and accommodation can intervene at this level, retrieving the presumptively missing meaning (Macagno 2011a; 2011b). A word can be thought of as an instrument to achieve a dialogical purpose, which at the same time carries a presumptive weight, resulting from an implicit reasoning from presumption. These two dimensions, the argumentative and the presumptive effect, are strictly combined. In the section above the argumentative force of a word has been described as a further move proceeding from the classification of reality. The classificatory word is the hinge between the act of defining reality (Schiappa, 2003) and the judgment on such fragment of reality that the speaker aims at eliciting. This move, however, is combined with a dialectical principle grounded on the concept of presumption: the burden shifting, or, as pointed out by Kauffeld, the "risk of resentment, criticism, reprobation, loss of esteem" cast on an interlocutor not accepting the word meaning (Kauffeld, 1998: 264). This presumptive effect of a word use is crucial for understanding Hamblin's treatment of ambiguity as charges of equivocation (Hamblin, 1970: 301). The use of a word is based on a presumptive reasoning filling the gap between the speaker's knowledge and the hearer's mind. On this view, the speaker presumes that the hearer knows and accepts the way a word is used. This presumption is grounded on two premises: 1) that the meaning of the word used (M1) is commonly accepted and shared by the community of speakers (meaning-sharedness premise), and 2) that the interlocutor accepts and knows the ordinary meaning of the words (rule of presumption). We can represent this reasoning as follows: Presumptive meaning Fabrizio Macagno 386 RULE OF PRESUMPTION: The interlocutor accepts and knows the ordinary meaning of the word W, unless W has been previously defined in the dialogue or is a technical term. MEANING PREMISE: W ordinarily means M1. PRESUMED MEANING: The interlocutor shall accept and know that W means M1. This presumptive reasoning shifts onto the interlocutor the burden of proving that M1 is not the accepted or acceptable definition of the word. On the other hand, the hearer can undermine the presumptive reasoning in three ways: 1) by attacking the presumptive rule; 2) by rejecting the shared meaning of the word; or 3) by challenging the uniqueness (in such a context) of the accepted meaning. The three types of attacks amount to implicit or explicit charges of equivocation. In the first two cases they are implicit, hidden behind a definitional counterargument, while in the third case the accusation is explicit. While in the first two cases the charge of equivocation needs to be borne out by reasons, in the third tactic the mere existence of an ambiguity constitutes evidence subjecting the presumption to default. The first strategy of rejection is frequently used in law, where the presumption of ordinary use is subject to default in two important cases described by two rules: the meaning of technical terms shall correspond to their technical use (based on technical dictionaries or expert opinion); legal terms defined elsewhere in the law or in a contract shall be interpreted according to their explicit legal definition. A clear case of charge of dialectical equivocation is when the hearer distinguishes two different meanings of the term used: the ordinary one, applied by the speaker to classify the case, and the legal one, used to draw the legal consequences of such a categorization. For example, we can consider the case Milkovich v. Lorain Journal Co. (497 U.S. 1, 1990), in which Milkovich, a high school wrestling coach, sued Lorain Journal Company's newspaper for publishing a "defamatory" article, in which the journalist expressed his opinion that "Anyone who attended the meet ... knows in his heart that Milkovich ... lied at the hearing." This statement reported a false fact, was advanced with reckless disregard to its truth or falsehood, and damaged Milkovich's reputation. For this reason it fell within the category of defamation (Gertz v. Welch, 418 U.S. 323, 1974). The defendant replied advancing an argument from classification. He claimed that since a statement of fact is opposed to an opinion, and a statement of fact is verifiable, opinion cannot be verifiable, let alone false. In appeal, the appellant (Milkovich) replied with a charge of equivocation that Hamblin and Equivocation 387 can paraphrased as follows (Milkovich v. Lorain Journal Co., 497 U.S. 3, 1990): Case 1: Attacking the rule of presumption The term "factual statement" in law has the particular meaning of statement "that relates to an event or state of affairs that existed in the past or exists at present and is capable of being known" (Ollman v. Evans, 750 F.2d at 981 n.22). Factual statements are in law not contrary to generic opinions, but to subjective assertions, or opinions grounded on personal evaluations. Opinions can report facts or value judgments: in the first case they are factual statements, as they are verifiable; in the second case they depend on speakers' values and therefore cannot be false. (Scott v News-Herald, 25 Ohio St 3d 243, 1986) The appellant therefore advances an attack that can be represented as follows: Lorain Journal Co. expressed an opinion reporting a false fact. Opinions are not factual statements1. (Ordinary definition) Argument from classification Lorain Journal Co.'s opinion did not express a false factual statement2. (Legal definition) The assertion of a false factual statement2 is essential to the classification of a statement as defamatory (punishable). Argument from classification implying legal consequences Lorain Journal Co.'s opinion was not defamatory (not punishable). The charge consists in accusing the appellee of using the ordinary definition of "factual statement" to classify what was reported on the column, but referring to its legal meaning when the legal consequences were drawn. The appellant grounded his charge of equivocation on an argument rejecting the presumption of ordinary meaning. Since "opinion" and "factual statement" were specified and defined in law, the presumption of ordinary meaning was maintained to fail. The unreasonableness of the appellee's argument was shown by distinguishing the two different meanings of "opinion," and was rejected proving the default of the presumption on which Lorain Journal Co. based its argument. The second strategy of rejection consists in refuting the proposed commonly accepted definition, or rather the fact that the proposed definition is more shared than its possible alternatives. In law, this strategy is used when the speaker aims at Fabrizio Macagno 388 showing that the legal interpretation of a concept amounts to a certain meaning M1, but the other party has classified his case using a different definition M2. Unlike the previous strategy, the speaker here does not challenge the rule of presumption, but the meaning premise. We can consider the case Muscarello v. United States (524 U.S., 1998), where a man was arrested while trafficking drug and transporting a gun in his car. According to the law, a person who "uses or carries a firearm during and in relation to a drug trafficking crime" (18 U.S.C. § 924(c)(1)) shall be condemned to a 5-year mandatory prison term. The crucial problem lies in the meaning of "to carry." The defendant interpreted it according to the presumed ordinary use as "carry on the person," and therefore claimed that the provision did not apply. The Court rejected the presumed shared meaning that the defendant used to classify the action under accuse, and claimed that it did not correspond to the actual and most common one. The Court had to face the existence in the ordinary use of two possible definitions of this term, "to transport" and "to carry on the person," both backed by the authority of famous dictionaries. The refusal of the word ambiguity and therefore the defendant's presumed meaning was based on the authority of newspapers, which are considered to mirror the common use of words: Case 2: Attacking the sharedness of meaning The New York Times, for example, writes about "an excon" who "arrives home driving a stolen car and carrying a load of handguns," Mar. 21, 1992, section 1, p. 18, col. 1, and an "official peace officer who carries a shotgun in his boat," June 19, 1988, section 12WC, p. 2, col. 1; cf. The New York Times Manual of Style and Usage, A Desk Book of Guidelines for Writers and Editors, foreword (L. Jordan rev. ed. 1976) (restricting Times journalists and editors to the use of proper English). [...] We recognize, as the dissent emphasizes, that the word "carry" has other meanings as well. But those other meanings, (e.g., "carry all he knew," "carries no colors"), see post, at 6, are not relevant here. And the fact that speakers often do not add to the phrase "carry a gun" the words "in a car" is of no greater relevance here than the fact that millions of Americans did not see Muscarello carry a gun in his car. The relevant linguistic facts are that the word "carry" in its ordinary sense includes carrying in a car and that the word, used in its ordinary sense, keeps the same meaning whether one carries a gun, a suitcase, or a banana. (Muscarello v. United States, 524 U.S. 125, 1998) Hamblin and Equivocation 389 The rejection of the defendant's argument is also in this case based on an implicit charge of equivocation, backed by an explicit counterargument aimed at supporting the difference between the definition used in the legal provision and the meaning considered in the defendant's classificatory argument. The last strategy amounts to what Hamblin refers to as a charge of equivocation, and corresponds an explicit disagreement on the identity of the word meaning used in the classificatory argument and in the further argument (from values, practical reasoning, etc.). This charge can be also referred to using the ancient dialectical notion of distinguo, in which the speaker distinguishes between two possible meanings of a word, agreeing to the argumentative consequences of one of them and disagreeing with the argument built on the other. An example of this dialectical strategy is the following dialogue between Rosaura and Florindo taken from Goldoni's play La donna di garbo (emphasis and translation mine): Case 3: Attacking the uniqueness of meaning Ros. I prove the major premise: "Consent, and not copulation, is an essential feature of marriage," as stated in the Laws on marriage, Compendium of legal rules. But the fact is that Tizio consented to marry Lucrezia; therefore Tizio shall marry Lucrezia. Flo. I distinguish the major premise "Consent, and not copulation, is an essential feature of marriage": if it means legal and solemn consent, I agree; if it refers to verbal agreement, I disagree. Ros. I counter this distinction: "Only naked consent is necessary for the constituting a betrothal"; article number four, Compendium on Betrothal. Therefore, Tizio shall marry Lucrezia. Flo. I distinguish the premise: "Only naked consent is necessary for constituting a betrothal." If it means "constituting a future betrothal," I agree; if it means "constituting an actual betrothal," I disagree. (Goldoni, 1829: 79-80)4 4 Original text: Ros. Probo mojorem; nuptias, non concubitus, sed consensus, facit; lege nuptias, digestis de regulis júris; sed sic est, che Tizio prestò 1' assenso nel promettere a Lucrezia; ergo Tizio deve sposar Lucrezia. Flo. Nuptias, non concubitus, sed consensus, facit, distinguo majorem; consensus solemnis et legalis, concedo; consensus verbalis, nego. Ros. Contra distinctionem: Sufficit nudus consensus ad constituenda sponsalia; lege quarta, digestis de sponsalibus; ergo Tizio deve sposar Lucrezia. Fabrizio Macagno 390 Florindo advances two different charges of equivocation in Hamblin's sense, pointing out a polysemy of the terms "consent" and "betrothal." "Consent" can refer to both a formal and informal agreement, while "betrothal" in the ancient laws on marriage could be used to refer to a form of engagement, called "future betrothal" (to be later ratified by copulation) and a civil marriage (De Sponsalibus, Ch1: 459A-460A). Florindo does not attack the argument, but simply rejects the presumption of a unique meaning shared by the interlocutor. He points out the dialogical equivocation between the argument brought forward by Rosaura and the one that he can accept. In this case, this move is possible because in the discussion it was not specified whether "consent" and "betrothal" were legal terms, defined by law, or ordinary words. The burden of clarifying the ambiguity shifts onto Rosaura, who supports her definition on the basis of legal provisions. 6. Conclusion Equivocation is a strategy frequently used in everyday conversation, political discourse and legal discussions. As seen in the examples provided, it is based on a difference between the speaker's and the hearer's meaning. The speaker uses a word with a new or uncommon meaning, and leads the interlocutor to interpret the sentence (and draw a conclusion from it), or the whole argument, using the commonly shared definition. Hamblin departed from the traditional logical approach to this fallacy and analyzed equivocation as a point of order, underscoring its fundamental dialectical dimension. However, in his account he suggested some views that exceeded the boundaries of the study of fallacy. In particular, he showed how presumptions, such as the presumption of meaning-constancy, are at the basis of dialectics and represent the necessary conditions of a meaningful discourse (Hamblin, 1970: 295). In this paper, this approach was extended and used as a starting point for investigating the argumentative structure of interpretation. The concept of presumptive meaning, set out in Hamblin's proposal of dialectical meaning, can provide an explanation for the possibility of bridging the gap of the impossibility of knowing the other mind. Both the speaker's move and the hearer's interpretation can be considered as guided by the presumption of Flo. Sufficit nudus consensus ad constituenda sponsalia, distinguo; ad constitutenda sponsalia de futuro, concedo; ad constitutenda sponsalia de presenti, nego. (Goldoni, 1829: 79-80) Hamblin and Equivocation 391 ordinary meaning. On the one hand, the speaker presumes that the hearer knows the meaning of the words he used, because they correspond to the ordinary (in the given community of speakers) meaning (in context). On the other hand, the hearer interprets the words on the basis of the presumption that the speaker is using them according to their ordinary usage (in context). This account of meaning can also explain the possible manipulative moves based on equivocation and the dialectical effects of using a word. Equivocation can be considered as an argumentative, dialogical and dialectical phenomenon that involves two patterns of reasoning: an argument from consequences and a further move, usually corresponding to an argument from values (or practical reasoning). Equivocation has a reasoning dimension, as it involves the use of two different meanings of the same word for two different patterns of argument, governed by different presumptions. 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