Lying with Uninformative Speech Acts

I propose an analysis of lying with uninformative speech acts. The orthodox view states that lying is restricted to assertions. However, the growing case for non-assertoric lies made by presuppositions or conventional implicatures challenges this orthodoxy. So far, the only presuppositions to have been considered as lies were informative presuppositions. In fact, uninformative lies were not discussed in the philosophical literature. However, limiting the possibility of lying to informative speech acts is too restrictive. Firstly, I show that standard, uninformative presuppositions can also be lies. Secondly, I extend this picture into uninformative lies made by declarative statements. To implement my proposal, I do not need a new definition of lying. Recently popular commitment-based definitions of lying are able to properly handle uninformative lies.


Introduction
Traditional definitions of lying maintain that one lies only if one says something one believes to be false with an intention to deceive. 1 Recently, there is an influential trend to modify this definition in two ways.Firstly, lies are not just any sayings; rather, the contemporary orthodoxy states that lying is restricted to asserting.Secondly, the intention to deceive is considered unnecessary.Thus, we are left with the following simple definition: lying is insincerely asserting. 2From these considerations we can extract the almost universally held assumption that underlies theorising about lying.

Paul's party
Dennis is going to Paul's party tonight.He has a long day of work ahead of him before that, but he is very excited and can't wait to get there.Dennis's annoying friend Rebecca comes up to him and starts talking about the party.Dennis is fairly sure that Rebecca won't go unless she thinks he's going, too.Rebecca asks Dennis: "Are you going to Paul's party?"Version A: (1) Dennis: No, I'm not going to Paul's party.

Version B:
(2) Dennis: I have to work.Rebecca comes to believe that Dennis is not going to Paul's party.
(1) is considered to be a lie, while (2) is merely misleading.One of the main criteria of a proper definition of lying is its ability to distinguish lying from misleading statements.As an example, take Stokke's (2018) definition of lying, which is based on a Stalnakerian (1974, 1978) theory of assertion: Stokke's definition of lying A lies to B if and only if there is a proposition p such that (L1) A says that p to B, and (L2) A proposes to make it common ground that p, and (L3) A believes that p is false.
Stokke's definition satisfies both the aforementioned assumptions.Conditions (L1) and ( L2) specify what it means to make an assertion and (L3) provides an insincerity condition.Thus, Stokke argues that lies are just insincere assertions.All examples of lies that Stokke provides are informative and, more importantly, INFORMATIVENESS follows from his definition.By his definition, (1) is a lie because Dennis says that he will not go to Paul's party and does not believe it, while (2) is not a lie because Dennis only implies that he will not go.Thus, Stokke's definition delivers the correct verdict.
Since INFORMATIVENESS is a crucial assumption behind Stokke's definition, let me expand on the idea that assertions are essentially informative speech acts. 6First of all, consider that many accounts of assertion propose a similar condition for a proper assertion, i.e., a proper assertion that p is such that p is not already common knowledge (for Searle [1969, 66], this is one of the "preparatory conditions" for asserting; for Stalnaker [1978, 88-89 in 1999], this is the first "principle" about assertion; and for Farkas [2022, 326], this is one of the "default contextual assumptions characterising canonical assertions").These theories maintain that it is infelicitous to assert a proposition that already belongs to the common ground.
Here are three further observations that corroborate the informativeness of assertions.Firstly, as mentioned in the introduction, there are unique conversational patterns that point to the informativeness of assertions, i.e., one can be criticised for asserting something that is commonly known (García-Carpintero 2004).For instance, if after saying (1), Dennis would come to Rebecca and just repeat (1), she could rightly criticise him by saying "I already know that," or "I know.You already told me that!"This shows that there is something improper and defective in uninformative assertions.
Secondly, there is an intriguing analogy between assertions and inquiries, i.e., inquiries can be seen as a reverse of assertions.Just as assertions are a default way of using a declarative mood, inquiries are a default way of using an interrogative mood.Further, just as assertions are essentially informative speech acts, inquiries are information-seeking speech acts-when asking a question, we expect to be informed.Finally, just as it is improper to assert information that is already commonly known, it is also improper to inquire when one already knows the answer.In short, while assertions are non-inquisitive and informative, inquiries are non-informative and inquisitive (Moyer and Syrett 2021;Farkas 2022). 7 Finally, consider the relationship between assertions and uninformative speech acts.It is improper to reassert the same content; however, such content can be reintroduced by means of uninformative speech acts, like reminding, or other types of content, like presuppositions.8Thus, it is improper for Dennis to reassert (1), but he can state the same content by reminding Rebecca that he will not come or by presupposing it.I will discuss such cases in detail in the subsequent sections. 9here are certain widely recognised criteria or tests for lying.Following them allows us to separate lying from misleading without relying on a certain definition of lying.For the present purposes, I will be using two.The first one is the so-called "deniability criterion."10It states that lies cannot be sincerely and consistently denied, only misleading statements can.In other words, whenever one does not lie but is merely misleading, one retains a plausible way to deny the accusation of lying.Thus, after saying (2), Dennis can respond something like this (Viebahn 2020,  733): (3) I didn't lie.I didn't claim that I wasn't going to go to Paul's party.I merely claimed that I had to work, which I did.
Viebahn acknowledges that (3) may seem pedantic, but it is consistent with Dennis's earlier statement.By contrast, Dennis is lying in (1) because he cannot consistently deny the content of (1).Consider that saying (4) does not work: (4) #I didn't lie.I didn't claim that I'm not going to Paul's party.
The second criterion is based on the observation of how assertions and lies are reported (see Holton  2019).It is not strictly speaking a test of lying (like the deniability criterion), but it helps make our intuitions about lying clearer.A proper way for reporting assertions is with a that-clause, but this does not work for lies.Consider the following: (5) Dennis said that he will not go to Paul's party.(6) #Dennis lied that he will not go to Paul's party.
(5) sounds natural and correctly represents the state of affairs.(6), however, sounds bad.The natural way of reporting lies is with about-clauses: (7) Dennis lied about not going to Paul's party.(8) #Dennis lied about having to work.
(7) correctly reflects what is going on in this case: by saying (1), Dennis lies to Rebecca about the fact that he is not going to the party.(8), on the other hand, is an infelicitous report since Dennis indeed had a lot of work.Thus, reporting (2) by an about-clause in (8) is a way of framing our intuitions and allows us to see that (2) is not a lie.

Lying with presuppositions
Let us focus on presuppositions.A presupposition is a piece of information that is taken for granted and commonly accepted.For instance, (9)-(10) presuppose the same thing, namely, that John owns a Mercedes.The difference between these cases is that the presupposition is carried by different triggers (i.e., factive verb and definite description, respectively): (9) I know that John owns a Mercedes.(10) John's Mercedes is new and shiny. 11esuppositions can be informative.Thus, I can introduce the information that John owns a Mercedes to my audience by presupposing this fact.If my audience notices that I presuppose a new piece of information, they can accept and accommodate it.Such a process is called presupposition accommodation. 12Crucially, all cases of presuppositional lies discussed in literature are based on this process (see Meibauer 2014; Viebahn 2020; Viebahn et al. 2021).Take the following example (Viebahn 2020, 735): Mercedes I Harry wants Rosa to think that his friend John is wealthy.In fact, John is not wealthy and does not own a car, as Harry knows very well.Harry asks Rosa: (11) Did you know that John owns a Mercedes?Rosa comes to believe that John owns a Mercedes.
(11) is a clear case of a presuppositional lie.In this example, Harry on purpose presupposes something he believes to be false.The criteria of lying deliver clear results here.Harry cannot sincerely and consistently deny presupposing that John owns a Mercedes.Saying something like (12) does not work (Viebahn 2020, 735): (12) #I didn't lie.I didn't claim that John owns a Mercedes.Some might disagree with Viebahn's judgment here and feel that (12) may not be quite as bad as (4).This is why it is good to consult also the second criterion.Harry's presupposition can be naturally reported in the following way: (13) Harry lied about John owning a Mercedes.Thus, we have at least prima facie reasons for accepting the possibility of lying with presuppositions.Viebahn (2020, 735-36), commenting on this case, makes three further points.Firstly, there seems to be no relevant difference between Harry's presupposition made in (11) and asserting the same information, as in ( 14): (14) John owns a Mercedes.Did you know that?Secondly, ordinary speakers strongly agree that Harry lies in (11).In an experimental study (Viebahn et al. 2021), stories like this received lie ratings of around 90 percent (Mercedes I included).The results remained on this level even when participants could classify these cases as not being lies, but merely misleading.Finally, even though presuppositional content is always carried by a certain speech act, it is important that (11) is a question.So, we cannot say that the lie is asserted.The content of questions is a set of propositions (see, e.g., Cross and Roelofsen 2020) and it is not suitable for lying.Thus, the only content in (11) that can be evaluated as a lie is presupposed. 13he presupposition in ( 11) is triggered by a factive verb.Before considering in detail how we can lie with presuppositions, consider one more case with a different trigger (Viebahn 2020, 738): Baby I Gertrude and Mick are colleagues of Jack, whose wife has recently given birth to a baby boy.Gertrude has seen the baby and knows it is a boy.She knows that Mick hasn't seen the baby and wants to trick him into thinking that John's baby is a girl.Gertrude says to Mick: (15) Jack's baby is lovely.Have you seen her yet?Mick comes to believe that Jack's baby is a girl.
(15) triggers the presupposition (by employing a gendered pronoun) that Jack's baby is a girl.Just as in the case of ( 11), this presupposition passes both criteria of lying.On the one hand, Gertrude cannot sincerely deny the presupposition made in ( 15). ( 16) sounds unnatural: (16) #I didn't lie.I didn't claim that Jack's baby is a girl.
Just as ( 12), ( 16) seems to contradict the original statement made in (15) and hence sounds improper.On the other hand, Gertrude's lie can be properly reported: (17) Gertrude lied about the gender of Jack's baby.
These two cases seem to provide an argument against ASSERTION-ONLY but are consistent with INFORMATIVENESS.In the rest of this section, I want to consider the question of why presuppositions are suitable for lying.
There are many ways of capturing the content of presuppositions.One take is to treat presuppositions as speaker commitments.It means that by presupposing p, one commits to the truth of the presupposed content and cannot deny it without contradicting oneself.For example, if Harry asks Rosa "Did you know that John owns a Mercedes?", he cannot later deny that John owns a Mercedes without contradicting himself.Interestingly, the degree of speaker commitment is similar in presupposed and asserted contents (Mazzarella et al. 2018; Reins and  Wiegmann 2021).However, while assertions contribute to at-issue content because they are a primary contribution in a context, presuppositions standardly contribute to non-at-issue content because their content is backgrounded (Simons et al. 2010).Because of that, presuppositions are subsidiary speaker commitments (Peters 2016).The situation slightly complicates when we consider informative presuppositions.They can have the same effects on the conversational background as assertions (see, e.g., Gauker 2008), however, they are distinct from assertions since only the latter are directly communicated (Kissine and Pantazi  2020). 14an a definition of lying capture presuppositional lies?Stokke's definition does not classify ( 11) and ( 15) as lies, for in neither case one says something one believes to be false.Stokke (2017)  explicitly argues that presuppositions cannot be lies for a simple reason: lies must be said, presuppositions are not, so they cannot be lies. 15This is very problematic since both cases pass the criteria of lying and Stokke himself follows the deniability criterion.Furthermore, as I just indicated, at least in some contexts, presuppositions can be as committal as assertions.In both cases, the speaker commits to the communicated content.Viebahn (2020, 743) recently proposed a commitment-based definition of lying that aims to capture presuppositional lies: A commitment-based definition of lying A lies to B if and only if there is a proposition p such that: (L1) A performs a communicative act C addressed to B with the content p; (L2) by performing C, A commits herself to p; and (L3) A believes that p is false.Viebahn (2020) explicates the notion of commitment by appealing to pretheoretical intuitions that are captured, among others, by the deniability criterion, i.e., if one commits to certain content, then one cannot consistently deny it without contradicting oneself.In his (2021, 307), he relies even more strongly on this criterion since the notion of commitment in lying is defined in terms of it.In the next section, I will discuss Viebahn's view on presuppositional lies, but now, even without going into details, it can be seen that his definition is able to explain all cases discussed so far.Just as Dennis lies in (1), it is equally so for Harry in (11), and Gertrude in (15).They are lying because each of them commits to p and believes that p is false.All of these cases meet INFORMATIVENESS.In the next sections, I will expand the realm of possibilities of lying into uninformative cases.

Lying with uninformative presuppositions
Take the following extension of the Mercedes case: Mercedes II Harry wants Rosa to think that his friend John is wealthy.In fact, John is not wealthy and does not own a car, as Harry knows very well.Harry asks Rosa: (11) Did you know that John owns a Mercedes?Rosa comes to believe that John owns a Mercedes.Later on that day, Rosa asks Harry about John and Harry says: (18) John's Mercedes is new and shiny.
The original story remains intact.What is different is the repetition of the presupposition from (11) in (18).However, this added presupposition is an uninformative one because Rosa already believes that John owns a Mercedes.Stating this presupposition again does not weaken Harry's commitment, rather it can reinforce this presupposition.To answer the question of whether ( 18) is a lie, consider the familiar criteria.Just as before, Harry cannot consistently deny claiming that John owns a Mercedes and ( 18) can be naturally reported as lying about John owning a Mercedes. 17he presupposition in ( 18) is triggered differently than in (11), i.e., by possessive construction.However, this only shows that lying is not restricted to a particular presupposition trigger.Instead of a declarative like (18), Harry could make any other statement that fits the context (for instance, an imperative utterance, "You must see John's new Mercedes!").
Uninformative lies can be characterised as lies with content that is already common ground.To emphasise, I am interested in cases of uninformative lies that will not be challenged as inappropriate. 18In principle, Harry can reassert to Rosa that John owns a Mercedes, but then he can be rightly criticised for making an uninformative assertion-Rosa could object and respond 16 See, e.g., Viebahn (2020, 2021); Marsili (2020); Reins and Wiegmann (2021); cf.García-Carpintero (2021). 17An anonymous reviewer notices that the intuitions regarding the report of Harry's lie may vary.Strictly speaking, a natural report of Harry's lie would be as lying about John's Mercedes being new and shiny.However, ( 18) is made in a specific context in which it is preceded by (11), and so when Harry says (18) Rosa already assumes that John owns the Mercedes.Thus, his second lie may be reported as lying about John owning a Mercedes. 18I am grateful to an anonymous reviewer for encouraging me to clarify this point.
something like "You already told me that!"However, it is perfectly natural to presuppose this information again and again (as in Mercedes II).In general, when lying, we do not want to be recognised as liars, and when our statement is challenged, as being in some sense inappropriate, we raise suspicion.Thus, an uninformative lie should be performed by means of a speech act that can transfer information that was already stated before.Presuppositions are a natural candidate for such cases because they are standardly treated as delivering already-known information.While one may presuppose information that is already commonly known, one cannot do so with assertions.This follows from an observation that "when it is correct to presuppose p, it is incorrect to assert it" (García-Carpintero 2020, 23).
It is worth noting that an initial lie can be made by uttering various speech acts, granted that they are suitable for lying.The options are not limited to assertions.In the introduction, I mentioned the possibility of lying with conventional implicatures. 19Thus, take Mercedes I or II and consider that instead of the first statement (11), Harry can communicate the same information by asserting (19) or conventionally implicating (20): (19) John owns a Mercedes.Did you know that?(20) John, who owns a Mercedes, is very handsome.
Once it is communicated that John owns a Mercedes, it is inappropriate to assert or conventionally implicate it again.Thus, ( 19) and ( 20) cannot be used as uninformative lies.
Before discussing some implications of lying with uninformative presuppositions, consider one more feature of uninformative lies.This time take the Baby I case with a minor alteration: Baby II Gertrude, Lily, and Mick are colleagues of Jack, whose wife has recently given birth to a baby boy.Gertrude and Lily have seen the baby and know it is a boy.They know that Mick hasn't seen the baby and want to trick him into thinking that Jack's baby is a girl.Gertrude says to Mick: (15) Jack's baby is lovely.Have you seen her yet?Mick comes to believe that Jack's baby is a girl.During the conversation, Mick inquires about Jack's baby and Lily says (21) She is very playful.
In this version, the uninformative lie is made by a different person than the initial lie.Everything else stays the same, i.e., in both cases, one presupposes something one believes to be false.Crucially, (21) carries an uninformative presupposition.Just as (15), it passes our criteria of lying.Lily cannot consistently deny claiming that Jack's baby is a girl and we can naturally report her lie as lying about the gender of Jack's baby. 20Moreover, when the same lie is not only repeated (like in Mercedes II) but is also made by various speakers it is reinforced even further, and thus it can be more compelling to the hearer to accept the presupposition.This shows that uninformative lies can be made in complex contexts and performed by multiple agents.
Let us return to the definition of lying.We saw that Viebahn's (2020) view captures informative presuppositions.What about uninformative ones?His definition seems to not make a difference between them.For him, lying about p is basically committing to p while believing that p is false.It is instructive to discuss his views on presuppositional lies both in his ( 2020) and (2021) papers.Viebahn repeatedly distances himself from the possibility of accepting lying with uninformative content.His argument rests on the idea that in uninformative cases, one does not commit to p and thus one is not lying.We can extract two parts of his argument.The first one states that presuppositional lies are assertions and the second that uninformative presuppositions cannot be lies.Let us consider them in turn.
For Viebahn, all analysed cases of "presuppositional lies are assertions" (2020, 744).He observes that "the commitment in lying can plausibly be seen as the commitment in asserting" (2020, 743), and he directly states that "[l]ying involves the committal speech act of asserting" (2021, 307).He says that because he wants to marry two ideas, i.e., that we can lie with presuppositions and that lying is restricted to assertions.Thus, he tries to keep both ASSERTION-ONLY and INFORMA-TIVENESS.His reasoning can be summarised in the following way: the traditional definitions of lying maintain that all lies are assertions, the newly presented cases involving presuppositions are lies too, thus, we must accept that presuppositional lies are assertions.
Consider the implications of Viebahn's view to the debates on assertion and presupposition.If Viebahn is right that the presented cases of presuppositions are assertions, then the classical definitions of assertion and presupposition are wrong.Many definitions of assertions have the so-called explicitness condition built-in, according to which, an assertion is a speech act that is explicitly presented (see, e.g., Alston 2000).This condition aims precisely at distinguishing between assertoric content that is at-issue and non-assertoric content that is not-at-issue; presuppositions or conventional implicatures belong to the latter.We have an analogical situation with definitions of presupposition where one of their main aims is to separate what is asserted from what is presupposed.
Viebahn's critique of all these views rests on the view that all lies are assertions.However, the fact that we can lie with presuppositions can simply be interpreted as working against the standard definition of lying, and so against ASSERTION-ONLY.In fact, this was already pointed out by Meibauer (2014).Moreover, Viebahn assumes the primacy of the definition of lying over the analogical definitions of assertion and presupposition.I do not see why.Take the explicitness condition in a definition of assertion.Viebahn (2020, 744-45) criticises such a condition since it disqualifies presuppositions from assertions.However, this is precisely the point of such a condition.The same can be said about defining presuppositions.There is widespread agreement among philosophers and linguists that asserting and presupposing are distinct ways of expressing content. 21Viebahn needs more to undermine this distinction than just referring to the traditional definition of lying.Thus, I do not see good reasons to accept Viebahn's view that presuppositional lies are assertions.
What about Viebahn's view that there is a difference in commitment between informative and uninformative cases?This is what he says: … there are different ways of committing oneself to a proposition: one can commit to p by saying p, but (in at least some situations) one can also do so by presupposing p, e.g. if p was not previously accepted in the conversation… .it seems plausible that speakers are not always committed to what they presuppose.For example, if a speaker goes along with a presupposition that is already part of the common ground, then she may not be committing herself to it.(2020, 743)   In both parts of this quotation, Viebahn seems to say that one commits to presuppositions if they are informative, but it is possible to not commit to presuppositions when they are uninformative.In fact, the latter is repeated throughout the article.Here I want to focus on Mercedes II and Baby II, which are cases of lying with uninformative presuppositions.In the last quoted statement, Viebahn entertains a case like Baby II, where Lily goes along with the presupposition that is already part of the common ground.By this view, such cases are not necessarily committal.But if they are not committal, they cannot be lies.However, from the context, it is clear that Lily is lying.In Mercedes II, it does not really make sense to say that Harry commits to what he presupposes only the first time.
In his (2021, 300), Viebahn adds one more condition to his definition of lying, i.e., an intention to communicate p to the hearer.This condition, Viebahn suggests, can be fleshed out in a Stalnakerian framework where a communicative intention p is an intention to propose p as an update to the common ground.I already mentioned, when discussing Stokke's definition, that the common ground view treats assertions as informative speech acts, and hence accepts INFORMATIVENESS.This reasoning can be seen in the following condition that Viebahn formulates: "… agents do not intend to communicate p … if they presuppose p while taking p to be common ground" (2021, 301).Consider again the second presuppositions in Mercedes II and Baby II; Harry and Lily satisfy Viebahn's condition, i.e., they presuppose something that they know is already a part of the common ground, which excludes the possibility of lying.However, intuitively they do lie.This condition is important because it is formulated in a more direct way than in (2020).In both cases, the result is the same.Viebahn's view precludes the possibility of lying with uninformative content.
The upshot is that presuppositional lies are not reducible to assertions, and thus we must drop ASSERTION-ONLY.Moreover, restricting lies to informative presuppositions, as Viebahn proposes, is untenable.Uninformative presuppositions are just as good vehicles for lying as informative ones. 22Notice that Viebahn's commitment-based definition of lying, or similar definitions of lying formulated in commitment terms, 23 can account for the presented cases.All that must be done is dropping the requirement of informativeness.In the next section, I expand the picture of uninformative lies to lies made by declarative statements, i.e., to such speech acts as reminding or guaranteeing.

Lying with uninformative speech acts
We can lie with all speech acts that entail the illocutionary force of assertion (see, e.g., Marsili 2020;  Viebahn 2021).This should extend the possibility of lying to speech acts whose commitment is at least as strong as in the case of assertions, thus to such speech acts as warning, guaranteeing, or swearing.Although for different reasons, both Marsili (2020) and Viebahn (2021) argue that the aforementioned speech acts are assertions.Thus, when I warn or guarantee you that p I do that by asserting that p.The conclusion is a familiar one, i.e., if lying is restricted to assertions, the above cases are informative speech acts. 22The question which presuppositions are committal deserves a separate discussion, but it seems that not all presuppositions are committal, and thus we can presuppose something that we believe to be false without lying.For instance, Stalnaker (1999,  100) gives an example of uninformative presupposition that is false but irrelevant-it is made just to facilitate communication.Noncommittal presuppositions can also be informative, which is shown by Donnellan's famous Martini case where one presupposes something one believes to be false (by using a definite description "the man drinking the martini") without lying.There is thus the need to separate committal from noncommittal presuppositions.One way of accounting for such cases is to argue that one lacks commitment in these cases and thus cannot lie.An alternative is to propose that in those cases one lacks an intention to deceive.For a discussion of such cases, see Gaszczyk (2023, chap.5).
The other issue that concerns lying with presuppositions is considering how different presupposition triggers influence the strength of the commitment.Presuppositional triggers can be classified along many dimensions, for instance, strong versus weak (Glanzberg 2005).Strong triggers (like factive verbs) carry a high level of commitment that can entail, for example, less chance of plausible deniability.On the other hand, weak triggers (such as additive particles, like again), in some contexts, can carry such commitment that could allow for deniability.If presuppositional commitment is gradable in such a way, the open question is whether some weak presuppositions should be considered as lies.There is thus a possibility that not all presuppositions are suitable candidates for lying.I leave this issue for future research.For a gradable notion of commitment in lying, see, e.g., Marsili (2014).
I propose to expand this picture by discussing two types of uninformative speech acts.Firstly, there are unique speech acts that are uninformative by design.Secondly, some speech acts can be both informative and uninformative, depending on the context.I will argue that both types of speech acts are suitable for lying. 24 paradigmatic case of a uniquely uninformative speech act is the speech act of reminding.Here is a standard case.By reminding you about the dentist appointment, I indicate that this piece of information has already been in the common ground, but I have a reason to believe you might have forgotten about it.Various speech act taxonomies classify reminding either as a special case of assertion or as a distinct speech act type (see, e.g., Searle and Vanderveken 1985; Alston 2000).What matters for the present discussion is that reminding does not provide a new piece of information into the common ground (Abbot 2008; cf.Stalnaker 2008; Clapp 2020). 25Looking from the perspective of informativeness of assertion, it is natural to treat reminding as a distinct speech act type from assertions.This is not a merely taxonomical issue.If assertions are essentially informative speech acts, uninformative assertions are incorrect.Thus, if reminders are assertions, they are in some sense incorrect.However, this is not the case.It is correct and perfectly natural to remind you about your dentist appointment. 26aving said that, consider how we can lie by reminding something.We need only a small alteration in the already familiar case: Mercedes III Harry wants Rosa to think that his friend John is wealthy.In fact, John is not wealthy and does not own a car, as Harry knows very well.Harry asks Rosa: (11) Did you know that John owns a Mercedes?Rosa comes to believe that John owns a Mercedes.Later on that day, Rosa asks Harry about John and Harry says: (22) Just wanted to remind you that John owns a Mercedes.If (22) for someone does not sound natural enough, it can be modified accordingly.Rosa can also explicitly ask Harry, "Can you remind me what car John owns?" and thus elicit a reminder as a response.Reminding passes the familiar criteria of lying.Harry cannot consistently deny claiming that John owns a Mercedes and his reminding can be naturally reported as lying about John owning a Mercedes.Crucially, ( 22) is an uninformative statement. 2724 I am grateful to an anonymous reviewer for encouraging me to elaborate on this point. 25I do not claim that reminding or any other uninformative speech act is uninformative in every sense.My focus is on (un) informativeness on the level of content, i.e., whether p is already part of the common ground.Uninformative speech acts play a variety of functions, e.g., they reintroduce a particular topic, or focus our attention on a topic under discussion.Furthermore, repeating the same content can reassure the audience to act on its basis and commit the speaker even stronger to what is communicated.
26 Consider the following reason for treating reminding as a distinct speech act type.One of the widely accepted arguments for individuating speech acts comes from the observations of their conversational patterns.For instance, assertions can be challenged by the "How do you know?" question.Advocates of the knowledge norm of assertion (e.g., Williamson 1996) have a simple explanation for such a challenge: if knowledge is the norm of assertion, then asking for one's knowledge is appropriate.Furthermore, I said that there are unique conversational patterns associated with informativeness of assertions.If assertions are informative speech acts, we can naturally explain why hearers can criticise us if we say something that is already known.Finally, consider reminding.We can, for instance, ask to be reminded of something ("Can you remind me when my dentist appointment is?"), or criticise someone for not doing so ("You should remind me about my appointment!You know how bad I am with remembering dates!").These conversational patterns make sense only in contexts when information that is reminded of was previously asserted.
27 Reminding is merely an example of a speech act in which we can repeat information that already belongs to the common ground.Another example of an essentially uninformative speech act is confirming or corroborating.Imagine the context of Baby II, where one person lies and another is repeating the lie.Instead of presupposing the same content (the presupposition in Baby II was triggered by a gendered pronoun), the second speaker can corroborate what was already said (e.g., by saying "Yes, she is lovely").Thanks to Manuel García-Carpintero for suggesting this example.
The second group of speech acts that can be used as uninformative lies contain speech acts that can be both informative and uninformative.I illustrate it with the speech act of guaranteeing.We rarely use speech acts with stronger commitment than assertions.It is broadly accepted that in asserting that p we represent ourselves as knowing that p (e.g., Williamson 1996).This is sufficient for most communicative contexts.However, sometimes context requires holding a stronger position or we want to indicate that our position is stronger than knowledge (say, we want to show that we are certain, or emphasise that we do know what we say).For instance, if I want to learn how to dive and know that you have some experience but do not know how substantial your experience is, you can either assert that you are a certified trainer or guarantee it to reassure me that I am safe with you.In both cases, you convey the same information.
One way to theorise about guaranteeing is to treat it as a speech act that reinforces an assertion (e.g., Turri 2013).Thus, I can firstly assert that p, and later on, guarantee that p. Guaranteeing in this sense does not deliver new information, rather it repeats and reinforces the content that was already stated. 28Having said that, consider a case of lying by guaranteeing.

Mercedes IV
Harry wants Rosa to think that his friend John is wealthy.In fact, John is not wealthy and does not own a car, as Harry knows very well.Harry asks Rosa: (11) Did you know that John owns a Mercedes?Rosa comes to believe that John owns a Mercedes.But remembering that she saw John at a bus stop the other day, she inquiries further about John and his car.Harry responds by saying: (23) I guarantee you that John owns a Mercedes.
By repeating the same information in (23), Harry commits even stronger to the truth of this proposition than by presupposing it in (11).Notice that, just as in the case of reminding, there are more options to express guaranteeing.One is by saying "I know that p" (Austin 1946; cf.Turri 2013), as in "I know that John owns a Mercedes."Finally, (23) passes the tests of lying.Here too Harry cannot consistently deny the content of (23) and his guaranteeing can be reported as lying about John owning a Mercedes. 29here are more speech acts that can be used uninformatively.Instead of (23), Harry can utter (24) or (25) which are also clear cases of lying: 30 (24) I assure you that John owns a Mercedes.(25) I swear that John owns a Mercedes.
As a final note, consider what Viebahn and Stokke have to say about the analysed cases.Neither of them engages in the discussion of whether lying is possible with uninformative content.Viebahn argues that one does not commit to p if p already is a part of the common ground (2020, 743).This equally concerns the content that is presupposed, reminded, or guaranteed.Stokke's view gives a different verdict to uninformative lies that are made with presuppositions and declarative statements.He explicitly argues against counting presuppositions as lies (2017,  2018) because presuppositions are not said (in the relevant sense, see section 2).The content of 28 Cf.footnote 25. 29 Another example of guaranteeing is provided by Turri (2010) in the discussion between invariantism and contextualism concerning knowledge ascriptions.Intuitively, in a "low-stakes" context, asserting that p is sufficient (as in the famous DeRose's bank case, "The bank is open on Saturday mornings"), while in a "high-stakes" context it is not; with rising stakes, we seem to need more than flat-out assertions that p. Turri proposes that what is required in the high-stakes contexts is guaranteeing that p. Importantly, the content of both speech acts remains the same.
30 I discussed cases that can be used as uninformative lies.Although this matter is contextual, some declaratives cannot be used in this way.For instance, if I warned you or agreed with you, it seems inappropriate to warn or agree with you again.For more on lying with explicit performative statements, see Marsili (2020).( 22)-( 25) is said,31 thus these statements should be considered lies.However, Stokke follows Stalnaker in defining an assertion as a proposal to update the common ground.The content of ( 22)-( 25) cannot update the common ground since this content already belongs to the common ground.32Thus, Stokke's view predicts that ( 22)-( 25) should be infelicitous.However, these statements are perfectly appropriate to make.Thus, Stokke's definition delivers wrong predictions to lies made by uninformative declarative statements.

Conclusions
My main aim was to make a case for lying with uninformative speech acts.Firstly, by showing that we can lie with presuppositions, I argued that lying is not restricted to assertions.Secondly, I made a case for the possibility of lying with uninformative presuppositions.This created the space of extending the domain of uninformative lies to other speech acts, for which I have argued in the final section.By arguing for uninformative lies, either made by presuppositions or by declarative statements, I wanted to point at a so far neglected phenomenon of lying with content that is already common ground.This revealed a crucial assumption behind some prominent definitions of lying.As it is widely assumed, lies are insincere assertions.But how an assertion should be understood is not always explicitly presented.I focused on one aspect of assertions, i.e, their informativeness.This discussion shows that more research has to be done into our understanding of the division between informative and uninformative content, and how it influences the concept of lying.