3.1. Ostensive communication

This study is performed within relevance theory (Sperber & Wilson Reference Sperber and Wilson1995, Wilson & Sperber Reference Wilson, Sperber, Horn and Ward2004, Wilson Reference Wilson2014, Carston Reference Carston2002, Reference Carston, Russell and Fara2012). Relevance theory is a theory about the mental processes involved in comprehending what is called ostensive communication. Consider examples (13)–(16):Footnote ⁴

1. (13)

   1. A: Do you want to play squash?

   2. B: I have an injured leg and can’t play.

2. (14)

   1. A: Do you want to play squash?

   2. B: [Deliberately and openly shows that his leg is bandaged.]

3. (15)

   1. A: Do you want to play squash?

   2. B: [Deliberately and openly shows that his leg is bandaged while saying:] With this leg, I can’t play.

4. (16)

   1. A: Do you want to play squash?

   2. B: [The leg bandage is visible to A, but B does not deliberately show it] Sorry, I can’t play.

In all of these examples, B communicates that he does not want to play squash, and he does this in a way that A can also understand the reason why B declines A’s invitation to play squash: B has an injured leg. However, there is a difference between (13)–(15) and (16). In (13)–(15), B overtly points out that his leg is injured and that he intends to point to this fact as the reason for his refusal. In (16), B does not overtly point to or mention his injured leg. The fact that his leg is injured is in evidence for A. Therefore, A can guess that B’s leg injury is the reason why B does not want to play squash, but there is nothing in B’s communicative act that requires A to notice the injured leg and make the inference as to the relation between this fact and B’s refusal. In the terms of Sperber & Wilson (Reference Sperber and Wilson2015:119), we can say that in (13)–(15), B has ostensively communicated both that he does not want to play squash and that his reason for this refusal is that his leg is injured. In (16), on the other hand, B has ostensively communicated only that he does not want to play squash. Although A can infer with reasonable assurance what B’s reason for the refusal is, B has not made overt any intention that A should make this inference. The intention to communicate what his reason for the refusal is was not made overt by B.

From these observations, we can derive a preliminary definition of ostensive communication, a definition that I will make more precise below. To ostensively communicate something means to make overt an intention to inform an audience of a certain piece of information. This means that a communicator engaging in an act of ostensive communication has two intentions: an informative intention, which consists of an intention to inform the audience of a certain piece of information, and a communicative intention, which consists of an intention to make the informative intention overt. Sperber & Wilson (Reference Sperber and Wilson1995:60–61) point out that making an intention overt amounts to inform the audience that one has this intention. Therefore, the communicative intention can be formulated as a second-order informative intention: an intention to inform the audience that the communicator has the informative intention I. A final step in making the definitions of the informative and communicative intentions of communicators precise is to specify in more detail what it means to inform an audience of something. I will take this step shortly, but first let us pause to consider some important traits of ostensive communication.

First, acts of ostensive communication—i.e. ostensive stimuli—provide the audience with only partial evidence of the communicator’s informative intention. The audience needs to access further contextual information to infer the intended meaning. This is blatantly obvious in (14), but in (13), the audience would have to infer (at least) what the relation between the conjunct expressions I have an injured leg and [I] can’t play is (that the first may count as a reason for the communicator’s inability to play squash); that [I] can’t play should be understood as [I] can’t play squash today; and that by stating his inability to play squash as a result of his leg injury, the communicator intends to convey a negative answer to A’s question. Because ostensive communication always requires the audience inferring communicators’ intentions, Sperber & Wilson (Reference Sperber and Wilson1995) use the more explicit phrase ostensive-inferential communication. A central concern for a theory of ostensive-inferential communication is to explain how the human mind can infer communicators’ intentions with sufficient reliability. Indeed, accounting for our comprehension of ostensive communication has been a central concern of relevance theory since its beginning.

Second, verbal communication is a particularly powerful instance of ostensive communication, powerful in the sense that the partial evidence that verbal ostensive stimuli provide for the communicator’s informative intention can be rather nuanced by the use of linguistically encoded meaning. While linguistically encoded meaning always under-determines the speaker’s meaning (Sperber & Wilson Reference Sperber and Wilson1995, Carston Reference Carston2002) and thus never provides more than partial evidence for the speaker’s intended meaning, verbal utterances provide much more fine-grained inputs to the inference processes involved in comprehending ostensive stimuli than non-verbal stimuli. Indeed, because natural language expressions cannot be used in communication apart from being used as ostensive stimuli providing input to cognitive inference processes, it can be expected that natural language is optimised for this interaction with the pragmatic inference systems. One area in which relevance theorists have been exploring this idea of optimal interaction between natural language semantics and pragmatic processing is the study of procedural meaning in the sense of Blakemore (Reference Blakemore1987, Reference Blakemore2002). Blakemore argues that some natural language expressions may encode a meaning of a special type by providing information about what inferences the conceptual meaning provided in the utterance feed into. The semantic analyses of the Norwegian particle jo and the German particles ja and doch that I will use as the point of departure for my analysis of the comparative pragmatic observations on the use of these particles in (1) and (2) make use of this notion of procedural meaning. I will explain this in more detail at the appropriate places in this paper.

Third, the communicative consequences of an act of ostensive communication depend not only on the audience’s comprehension of the communicator’s informative intention. In (13), for instance, the audience may correctly comprehend B’s intention to make them understand that the reason for B’s refusal to accept A’s invitation to squash is that his leg is injured. However, it makes a difference for A if he believes that the statement I have an injured leg is true or not. If A accepts it as a true statement, he will accept B’s refusal as being based on a justified reason. If A does not accept the truth of this statement, then he will treat B’s refusal as being based on a cheap excuse. The difference this makes in the social interaction between A and B is obvious. Because the audience’s judgements about the credibility of ostensively communicated information have such obvious consequences, Sperber et al. (Reference Sperber, Clément, Heintz, Mascaro, Mercier, Origgi and Wilson2010) argue that a theory of ostensive communication must not only account for how the audience comprehends the communicators’ informative intention but also for how the audience makes inferences about the trustworthiness or believability of communicated information. They argue that there is evidence that the human mind uses a variety of specialised cognitive mechanisms dedicated to exercise epistemic vigilance on the part of the audience. These cognitive mechanisms are triggered by ostensive stimuli just as comprehension mechanisms are, and they work largely in parallel to the inference processes involved in comprehension. One important component of epistemic vigilance is a mechanism devoted to process arguments, i.e. inferences identifying warrant relations between claims that the individual is not prepared to accept at face value and beliefs that may support those claims. Argumentation obviously plays an important role in the text that is at the centre of this paper (see example (1)). Indeed, I will argue that difference in usage of Norwegian jo, on the one hand, and German ja and doch, on the other, results from differences in which the semantically encoded meaning of the respective particles interacts with inferences employed in argumentation.

3.2. Comprehending ostensive communication

The central issue for a theory of ostensive-inferential communication is to account for how our mind can infer the communicator’s informative intention. After all, the non-demonstrative inferences involved in this process are inferences to the best explanation, and a single ostensive stimulus (utterance) may be contextualised in different ways, leading to many different possible inferences. Although verbal communication sometimes fails because the audience may infer meanings that communicators did not intend to convey, ostensive communication is remarkably successful. Sperber & Wilson (Reference Sperber and Wilson1995) argue that this is because ostensive communication comes with a specific claim to relevance (in a technical sense) that can easily be verified by the mind following a simple and fast cognitive heuristic procedure.

The notion of relevance involved is a technical one: An input to cognitive processes is relevant to the degree that it has many positive cognitive effects (i.e. true improvements of the individual’s representation of the world that can only be derived by processing the input against a set of contextual assumptions), and the processing effort to achieve these effects is low (Sperber & Wilson Reference Sperber and Wilson1995:265–266).

Relevance in this technical sense is what our mental processes look for in processing inputs. Ostensive stimuli are a special type of input: they are pieces of overtly intentional behaviour. They are not relevant unless we can ascribe specific informative and communicative intentions to the communicator. This in turn means that the mind must inferentially process these inputs. However, because according to the cognitive principle of relevance the mind attends to those inputs that are maximally relevant, this means that ostensive stimuli must come with a specific claim of relevance. They must be at least relevant enough to be worth the audience’s processing effort. However, communicators that want to be understood should strive to make their ostensive stimuli even more relevant than that. They cannot make their stimuli more relevant than their abilities and preferences allow. Consequently, ostensive stimuli come with a tacit claim to what Sperber & Wilson (Reference Sperber and Wilson1995) call optimal relevance: the ostensive stimulus is at least as relevant for the audience to pay attention to and, moreover, the most relevant one given the communicators abilities and preferences. This is the communicative principle of relevance (Sperber & Wilson Reference Sperber and Wilson1995:270).

The communicative principle of relevance is a claim about the level of relevance that a given ostensive stimulus will achieve for the audience. Comprehending ostensive stimuli means verifying this claim. The most obvious way to verify this relevance claim, and thereby go about comprehending the ostensive stimulus, is to apply the following procedure (Wilson & Sperber Reference Wilson, Sperber, Horn and Ward2004:614–617): First, access the interpretive hypothesis that is most easily accessible to the audience. An interpretive hypothesis is a set of hypotheses about the propositions that are explicitly and implicitly communicated. This includes hypotheses about reference assignment, variable assignment, free enrichment of the logical form, speech act and propositional attitude description, implicatures, and the contextual assumptions that are needed to warrant these inferences. Having accessed the most easily accessible interpretive hypothesis, the second step in the procedure is to check whether the utterance satisfies the audience’s relevance expectations. If it does, the audience is licensed to accept this interpretation as the author-intended one. If it does not, the audience will access other interpretive hypotheses in order of accessibility, following a path of least effort either until an interpretation satisfying the audience’s expectations of relevance are satisfied or until the process is abandoned because it causes gratuitious processing effort.

To illustrate how this heuristic works, consider how Per will comprehend Jessica’s utterance in (17):

1. (17) Per: Wasn’t that superb last night, how Andrew played the violin?

   Jessica: Well, he didn’t win the young talent’s prize for nothing.

Recognising Jessica’s utterance as an ostensive stimulus in response to his question, Per will understand that Jessica tacitly claims not only that her utterance is optimally relevant to Peter, but also that it is optimally relevant to Peter by addressing the question whether Jessica disagrees with Peter’s assessment that Andrew played very well in last night’s concert. Verifying this claim is straightforward by accessing the hypothesis that Jessica explicitly communicated the idea that John did not win the young talent’s prize for musicians by not playing above standard level and processing this against the contextual assumptions Winning the young talent’s prize requires performance well above standard level and Someone who performs well above standard level at a competition is capable to perform well above standard level in general. These contextual assumptions warrant the conclusion that John played well above standard level at the concert last night, and this conclusion manifestly satisfies the relevance expectations raised by Jessica’s utterance. Per is, therefore, justified to treat this conclusion as an implicature, i.e. as an implication that Jessica intended him to draw and attribute to her informative intention.

This explanation is only a rough sketch of how to account for how we comprehend Jessica’s utterance. In reality, the interpretations we arrive at are likely to be much richer in the sense that they weakly convey a range of implications, rather than merely a few precisely identifiable ones. I will touch on this issue in a moment when I consider the role of the particle well, which has a constraining function on the inferences that the audience is expected to draw from the utterance.

3.3. Procedural meaning

What is the place of linguistic semantics in this picture? Let us look at two different words in example (17) and ask what is their role in the comprehension process: nothing and well. The word nothing can be understood as linguistically encoding a schematic concept expressing the idea of an entity that does not exist. What this idea amounts to in the context of the expression for nothing needs to be determined in context.

The word well, on the other hand, has a signalling function: it signals that the utterance is more relevant in the accessible contexts than the audience may have anticipated (Blakemore Reference Blakemore2002:140–141). This signalling function works as follows: well raises the activation level of the relevance-theoretic comprehension procedure as a whole. This means that all the sub-heuristics or procedures that the mental comprehension module may use in working out the comprehension heuristic become more activated by the use of well. As a result, it requires less effort from the audience to compute more weakly communicated implicatures than it would have been without the use of this explicit trigger (Blakemore Reference Blakemore2002:140–141). Blakemore explains the meaning of well in her own words as follows:

Linguistic semantics is about what words or morphemes linguistically encode. Linguistic meaning feeds into pragmatic inference processes and supports the inferential phase of comprehension. The goal of linguistic analysis is to find out what it is that enables a given linguistic item to optimally support the inferential component of the pragmatic comprehension process. Sperber & Wilson express these ideas in the following words:

What I propose to do in this paper is to check the adequacy of the linguistic semantic analyses developed by Berthelin & Borthen (Reference Berthelin and Borthensubmitted) and Unger (Reference Unger2016a, Reference Unger2016b, Reference Unger2016c) of the Norwegian and German particles in question. These analyses were developed along the lines of the approach to procedural semantics outlined in this section. These analyses will be tested by way of exploring how well the semantic hypotheses that they make support the pragmatic processing of given examples. In this evaluation, an important question will be how well the given analyses explain the role these particles have not only in comprehension but also in argumentation.

3.4. Ostensive communication and argumentation

Ostensive communication with verbal utterances gives enormous benefits to human communicators. By means of this type of communication, people can acquire rich and nuanced information that they could not acquire by any other means. Moreover, this information—if true and accurate—could improve their mental representation of the world tremendously both in terms of quality and quantity. Besides, verbal ostensive communication can enable communicators exchanging information that makes them much more effective in coordinating cooperative behaviour. However, ostensive communication also exposes the audience to the risk of being intentionally or unintentionally misinformed. Having the mind infested with misinformation and no way to efficiently guard against this problem would undermine the benefits of ostensive communication. Sperber et al. (Reference Sperber, Clément, Heintz, Mascaro, Mercier, Origgi and Wilson2010) argue that the only rational approach for the audience to take in fighting this problem is to selectively allocate trust. This means that the audience varies between being more critical about the communicated information in some situations and being more disposed to be credulous in others. An audience that modulates levels of trust in this way exercises what Sperber et al. (Reference Sperber, Clément, Heintz, Mascaro, Mercier, Origgi and Wilson2010) call epistemic vigilance. The same authors go on to argue that our mind is equipped with a number of cognitive mechanisms dedicated to this task. Among them is what Mercier & Sperber (Reference Mercier, Sperber, Evans and Frankish2009:1541–57) call an argumentation module. The purpose of this cognitive mechanism is to link claims with chains of premises that support them.

Claims are statements that the audience is not prepared to accept at face value. The mechanisms of the argumentation module search for mental representations that could be inserted in the schema (18):

1. (18) P1 AND P2 . . . WARRANT CLAIM C

When the WARRANT relation is established between a series of representations and the content of the claim, the series of representations P1 . . . P2 will lead to the same logical inferences as representation C alone does, in any context. In other words, the series of premises (i.e. arguments) interpretively resembles and metarepresents the claim. The argumentation module is therefore a module dedicated to processing metarepresentations of a certain type.

To see how such an argumentation module may interact with comprehension mechanisms, let us look at an example taken from the advertisement in example (1). Intuitively, the first sentence conveys an explicit statement that also conveys the implication The audience should take the bus. Moreover, we get the strong feeling that this implication is not something that the audience should merely comprehend, but it is something that the communicator intends to persuade the audience of. How can we explain these two intuitions? Consider first the comprehension of the implicature.

1. (19)

   1. a. Explicit statement: One can save 17,000 NOK in a year by taking the bus instead of the car for getting into town for work everyday.

   2. b. Contextual premise: I am interested in saving costs.

   3. c. Contextual implication: I can save money by taking the bus instead of the car. (Follows from (19-a) and (19-b))

   4. d. Contextual implication: I should take the bus. (Follows from (19-b) and (19-c))

The first sentence of the advertisement in (1) conveys an explicit statement (19-a). This statement yields cognitive effects if processed in a context that contains assumption (19-b): in this context, (19-a) yields (19-c) as a contextual implication. Furthermore, the contextual implication (19-c) may be used as a premise together with (19-b) to yield yet another contextual implication (19-d). Because the explicit statement (on this interpretation) yields positive cognitive effects without incurring unreasonable processing effort, it can be accepted as an explicit statement the communicator intended to convey. Furthermore, because it is easy to see that with only minimal context extension, (19-d) yields more cognitive effects (outline what sort of behaviour changes would follow from taking the bus), this implicit conclusion can also be attributed to the communicator’s informative intention and accepted as an implicature.

However, the implicature amounts to a claim that the audience may not be prepared to accept at face value. This is, among other factors, due to the cognitive effects detailing behaviour changes that the audience would need to implement if they accepted that claim. True, the implicature (19-d) logically follows from the explicit content of the utterance and an easily accessible contextual assumption. But how strong is the inferential warrant that the implicature receives from these premises? This is where the argumentation module comes in. Having identified the implicature as a claim that the audience is hesitant to accept, the argumentation module looks for premises that may warrant the claim strongly enough to justify acceptance. The comprehension procedure has already selected an appropriate context. The most effort-effective path for the argumentation module is to start with those contextual assumptions and the logical relations that the comprehension procedure has established among them and evaluate the strength of the warrant relation that these premises may confer on the implicated conclusion. Having found that the premises (19-a), (19-b) and (19-c) indeed strongly warrant the conclusion (19-d), the audience is now confronted with the fact that it is inconsistent to hold on to belief in the mentioned premises and still refuse to accept the conclusion that I should indeed take the bus. Footnote ⁵

As this discussion makes clear, comprehension and argumentation evaluation are distinguishable processes that may work in parallel on ostensive stimuli. Wilson (Reference Wilson, Escandell-Vidal, Leonetti and Ahern2011) argues that linguistic procedural indicators may trigger (i.e. raise the activation level of) sub-procedures implemented not only in the comprehension module but also in the argumentation moduleFootnote ⁶. In particular, she accepts an argument made by Sperber (Reference Sperber2001) that inferential connectors such as English but, so, therefore and so on, should be analysed as triggering argumentation procedures directly.

However, because argumentation evaluation and comprehension work parallel in the way outlined above, processing procedures primarily related to comprehension may have a secondary effect on argumentation evaluation and vice versa. This means that it should be an empirical issue whether in a given language a certain inferential connector triggers a comprehension procedure or an argumentation procedure. Unger (Reference Unger, Wałaszewska and Piskorska2012) argues for this position by showing that by adopting this position, we can explain a number of intra-linguistic and cross-linguistic properties of certain inferential connectives and evidential particles. I will adopt this position in the present paper, showing that while jo, ja and doch affect argumentation evaluation, they do so in an indirect way.

4.1. Argumentative orientation in the semantics of the particles?

Because the difference in acceptability of jo, on the one hand, and ja and doch, on the other hand, appears to be connected with different functions of the utterance in argumentation, one may argue that the semantics of the particles must refer to argumentative orientation. For instance, it might be claimed that German doch and ja indicate a ‘negative’ argumentation orientation in the sense that the utterance is marked as providing reasons against a claim. Norwegian jo, on the other hand, does not specify this argumentative orientation. But this is difficult to maintain in the face of examples such as this:

1. (20) Diese Jungs aus Turin rocken. Waste Pipes sind sympathisch, spielen gut und werden ja schon mal als die heimlichen Nachfolger von Led Zeppelin bezeichnet.

   ‘These boys from Turin rock. Waste Pipes are congenial, play well and are (MP) sometimes already called the hidden successors of Led Zeppelin.’ (A09/JAN.00035 St. Galler Tagblatt, 03.01.2009, S. 34; Hin und Weg)

I do not see how the utterance with ja in (20) could be interpreted as involving an argumentation against a certain claim. On the contrary, ja occurs in the last of a series of three reasons to support the claim made in the first sentence of this example.

4.2. Mutual manifestness and common ground

It has long been recognised that these particles function to indicate what is ‘common ground’ between communicator and audience (Lütten Reference Lütten and Weydt1979, Fretheim Reference Fretheim1991, Fischer Reference Fischer, Fetzer and Fischer2006, Blass Reference Blass, Andersen and Fretheim2000). Sperber & Wilson (Reference Sperber and Wilson1995) argue that a cognitively realistic account of the informal notion of ‘common ground’ must be based on the notions of manifestness and mutual manifestness, rather than on notions of mutual knowledge or belief.

Manifestness is a property of inputs to mental processes or, in other words, pieces of information (Sperber & Wilson Reference Sperber and Wilson2015:133–135). A piece of information is manifest to the degree that the individual is capable of representing it mentally and accepting it as true or probably true. As I am typing this, I am able to see the Trondheimsfjord out of my office window. The water surface is visible in different colours, depending on the weather and position of the sun. Right now, the colour is some non-discript shade of greyish blue, not much contrasting with the colour of the sky. This fact is manifest to me. However, this fact does not much impact on my activities. I do not pay attention to it and most likely do not represent it in my mind. Other days, however, it happens that the same scene of the Trondheimsfjord may light up in such special colours that I cannot help but pay attention and look up in the middle of my work. In this case, the information that the water surface is visible in special colours is not only highly manifest to me but also manifest to a degree that I clearly do represent this fact mentally.

The totality of inputs to mental processes that are manifest to an individual at a given time is the individual’s cognitive environment (Sperber & Wilson Reference Sperber and Wilson2015:135) When two individuals meet and communicate, their cognitive environment overlaps: they may have shared memories from former conversations, and they may be able to draw on facts that they each have learned at school. If they meet in a face-to-face conversation, they will both be able to represent their common physical environment. In short, two individuals may have a shared cognitive environment (Sperber & Wilson Reference Sperber and Wilson2015:135) consisting of pieces of information that are accessible to them both.

The shared environment between individuals engaged in communication may have a subset of information about which it is also manifest to the individuals that they share it. Sperber & Wilson (Reference Sperber and Wilson1995:41–44) define this subset as the mutual cognitive environment. A piece of information is mutually manifest to communicator and audience to the extent that it is manifest in their mutual cognitive environment. For example, when you come to visit me in my office, it is immediately manifest that we share the information about what colour the water surface of the Trondheimsfjord has that moment. This is part of our mutual cognitive environment (although we may not represent this information), because it is manifest to both of us that we are capable of seeing the fjord from the office window. At the same occasion, you may notice a copy of a textbook on statistics on my desktop. You happen to have read this particular textbook a while ago. It will manifest to you that I most likely will have read a portion of this textbook, and this information will be in our shared cognitive environment. However, because it is not manifest to me that you have read this book as well, this information is not in our mutual cognitive environment. Consequently, in our conversation, you cannot say something to me that depends on knowing what is written in that particular book and expect me to immediately understand what you mean. In contrast, during our conversation in my office when the clouds suddenly clear and the sun lights up the fjord in amazing colours, I can exclaim Wow, what an amazing view! and expect you to understand what I was trying to communicate.

These very general considerations already suffice to illustrate that correctly estimating and keeping track of what is mutually manifest is an important task for communicators. One can therefore expect that languages may have developed expressions whose function is to indicate the degree of manifestness or mutual manifestness of certain pieces of information (Blass Reference Blass, Andersen and Fretheim2000). In sections 4.3 and 4.4, I will review the semantic analyses of the particles jo (Norwegian), ja and doch (German) that attribute to them the function to indicate in which way the information communicated is assumed by the communicator to be (mutually) manifest.

Finally, recall that manifestness is a matter of degree. Information may be more or less manifest to an individual, depending on two factors: first, the more accessible to mental representation or memory retrieval a piece of information is, the more manifest it is to the individual. Second, the stronger evidence is available for evaluating it as true, the more manifest it is. Therefore, we can expect procedural indicators of the degree of manifestness of a piece of information to fall into three types:

1. (21)

   1. a. Expressions indicating that the information conveyed is highly accessible.

   2. b. Expressions indicating that the information conveyed is strongly evidenced.

   3. c. Expressions indicating that the information conveyed is highly manifest as a result of all factors combined.

The analyses reviewed below argue that the respective particles under investigation realise these options in different ways.

4.3. Norwegian jo

According to Berthelin & Borthen (Reference Berthelin and Borthensubmitted), the Norwegian particle jo in its sentence internal position raises the activation status of two processing procedures. These procedures can be described as follows (rephrasing Berthelin & Borthen’s formal analysis slightly):Footnote ⁷

1. (22)

   1. a. Interpret the explicature of the utterance as mutually manifest to communicator and audience

   2. b. Interpret the explicature of the utterance as a premise for supporting some accessible assumption(s) q as implicature(s)Footnote ⁸

Applying this semantics to example (1) [a], we can account for the audience’s comprehension in the following way:

1. (23)

   1. a. The money you save, you can certainly use for something nice or useful.

   2. b. If taking the bus brings both personal and environmental advantages, then there are stronger reasons for taking the bus than the audience might have been aware of.

   3. c. Saving money for use on nice or useful things is a personal advantage.

   4. d. There are stronger reasons for taking the bus than the audience has previously been aware of.

   5. e. It is not the case that there are no good reasons for taking the bus.

The previous sentence explicitly stated that one can save money by taking the bus to work, and to the extent that the audience accepts this claim, the explicature of the utterance (that one can surely use saved money on something useful or nice) is already manifest to the audience. The particle jo indicates that this is indeed the intended interpretation, but it also triggers a search for some more implications. Additional premises like (23-b) and (23-c) are easily accessible and yield conclusions such as (23-d) as implicature. This implicature functions, in turn, as an argument to oppose the assumption There are no good reasons to take the bus in (23-e).

Applying the semantics to example (1) [b], we can explain the comprehension process in this way:

1. (24)

   1. a. You can read, work, relax, communicate and dream on board the bus.

   2. b. One can use the time on the bus for useful or pleasurable purposes in ways one could not when driving a car or riding a bike.

   3. c. If riding the bus to work has even more advantages than financial ones, there are even stronger reasons for taking the bus than the audience has previously been aware of.

   4. d. There are even stronger reasons for taking the bus than the audience has previously been aware of.

Assumption (24-a) describes something that the audience has most likely experienced before, something that is strongly manifest to him. Jo requires the audience to look for more implications that follow particularly from this assumption. Such implications can be gained from accessing easily available premises such as (24-b) and (24-c), which together yield the conclusion (24-d). This conclusion contextually strengthens the further conclusion (weak implicature) needed in processing (1) [a], thus increasing relevance by backwardly strengthening this conclusion.

Notice this point about implicatures, which are implications (conclusions or premises) that the communicator intends the audience to entertain. This means that they must be compatible with the communicator’s preferences (and abilities). For example, in a communication where the communicator persuades the audience of some point, only relevant implications that are conceivably in harmony with this goal of the communicator can be considered as potential implicatures. Thus, the constraint that the information marked by jo as more manifest should be used to derive further implicatures (i.e. the constraint in (22-b)) in effect restricts the search for further implications to those that may be consistent with the communicator’s manifest goals.

4.4. German particles ja and doch

Unger (Reference Unger2016a, Reference Unger2016b, Reference Unger2016c) argues that the German particles ja and doch have the following procedural semantics:Footnote ⁹

1. (25) Ja indicates that there is strong evidence for the truth of P.

2. (26) Doch triggers the following procedures:

   1. (a) increase the epistemic strength for P.

   2. (b) access a context containing NOT P

Both modal and non-modal uses of ja and doch (i.e. where the particle does not occur in the sentence medial position between the finite and infinite component of the verb) raise the activation level of these procedures. However, modal and non-modal uses of these particles raise the respective procedures to different degrees: in modal uses, the procedures are activated merely to some degree, whereas in non-modal uses, these procedures are activated to a higher degree. As a consequence, modal uses of these particles are relevant only in situations where it is useful for the communicator’s success that the manifestness of propositions conveyed in the utterance is raised to some extent, but not much. Such situations may involve argumentation, where persuasive arguments often can be made by explicitly referring to mutually manifest premises.

Why is it good for persuasive arguments to point out that the claim is warranted by mutually manifest assumptions (premises)? If a claim is warranted by some assumptions that both the audience and communicator take for granted (i.e. is highly manifest to them) and have reasons to think that they share them (i.e. is mutually manifest to them), then the audience has good reasons to accept this claim. Not doing so would imply revising a mutually manifest assumption, and this does not only involve a cognitive cost for re-assessing the validity of this assumption but also a social cost for rejecting some common ground (Unger Reference Unger, Oswald and Maillat2018). Therefore, it is of high persuasive value if the communicator can show the audience that her claim is warranted by premises that are part of their mutual cognitive environment.

Recall that manifestness involves two factors: epistemic strength and cognitive accessibility. Both ja and doch affect the manifestness of propositions by indicating the epistemic strength of these propositions. Therefore, applying either particle to an assumption that is already mutually manifest enough in context may bias the audience to seek the relevance of this move in the claim that the audience did not appreciate the factuality of the mutually manifest assumption.

This is in contrast to Norwegian jo, which affects the manifestness of propositions on the whole rather than selectively affecting the epistemic strength factor involved in manifestness. This is not likely to bias the audience into attributing to the communicator the belief that the audience did not appreciate the factuality of the mutually manifest assumption.