 Clearly, the ‘him’ in (43) can be interpreted as Phil or Stanley. But, crucially, how you interpret ‘him’ will depend on how you connect the two sentences. On the one hand, the interpretation of ‘him’ as referring to Phil goes hand in hand with a causal relation – its was the tickling that caused the poking (known as a result relation. Interpreting ‘him’ as referring to Stanley suggests goes hand in hand with a parallel relation. Of course the inference is defeasible – one can always break the connection between discourse relation and pronoun resolution in a manner that looks much like cancellation for Griceans (‘…Liz poked him, I mean, Phil, for unrelated reasons’). But the point is that the search for discourse relations that help settle pronominal reference is good evidence that the discourse relations are part of your linguistic knowledge, not just a reflect of cooperative conversation and maxim following or flaunting.  The study of discourse relations has flourished into a large literature in the last 20 years but the relevant point for us is that it looks like (43) is ambiguous as a discourse. This type of ambiguity is fairly novel and much work is still needed to get clear on the number and nature of possible relations that provide the possible resolutions of ambiguities like (41).  4. Detecting Ambiguity  Now that we have separated types of ambiguity, we may reasonably ask how we tell when a term or phrase contains an ambiguity. The answer may be disappointing – there are tests and considerations but no firm answers and probably a lot depends on what the ‘best theories’ in linguistics etc. end up looking like. Nevertheless, we can make some progress. The canonical source for these tests is Zwicky and Sadock’s ‘Ambiguity Tests and How to Fail Them’ (1975).  These tests generally depend on the presence or lack of interpretations and on judgments regarding the ridiculousness of interpretation (the absurdity of the meaning is known as zeugma – though it should probably be known as syllepsis). These judgments can be difficult to make, especially in tricky philosophical cases, so we must treat the results of the tests with care. 4.1 Conjunction Reduction  A standard test for ambiguity is to take two sentences that contain the purportedly ambiguous term and conjoin them by using the term only once in contexts where both meanings are encouraged. For example, ‘light’ is a predicate that can enjoy the same meaning as either ‘not dark’ or ‘not heavy’.  The colours are light. The feathers are light.   The following, however, seems to be zeugmatic:  ?The colours and the feathers are light.   The reduced sentence is zeugmatic for obvious reasons. This is evidence for ambiguity (or polysemy) in ‘light’. On the other hand, ‘exist’, which has been claimed to be ambiguous, seems not to display such zeugmatic effects:  Toronto exists. Numbers exist. Triadic relations exist. Toronto and numbers and triadic relations exist.   The test is limited in one way. If a term can be ambiguous but in a way so subtle that competent speakers may miss it, then the zeugma might not be noticeable. Given that these tests try to draw on linguistic judgments to detect ambiguity, it’s not clear how to proceed when there is a case of disagreement over the presence of zeugma.  We can use the test in cases in which one wouldn’t necessarily expect zeugma, but merely lack of multiple interpretations. For example:  Han and Chewbacca used superfluous hair removers.   (51) doesn’t allow a reading on which Han used a hair remover that was superfluous and Chewbacca used a remover of superfluous hair. If multiple interpretations are impossible, there is evidence of ambiguity. This is to be expected since the point of conjunction reduction is to ‘freeze’ the syntactic structure and in ambiguous cases, the effect is achieved.  As mentioned above, conjunction reduction has been used to argue that collective-distributive ambiguities are due to an ambiguity in the subject phrase. Consider:  John and Jane moved a piano.   One might think that the readings are generated by an ambiguity in ‘and’: sometimes it acts as a sentential operator and sometimes as a term-forming operator that makes two names into a single term for predication. However, notice that there are some predicates that can only be (sensibly) interpreted collectively, such as ‘met’:  John and Jane met for lunch.   In this case, there is no sense to be made of ‘John met for lunch and Jane met for lunch’ and so the sentential conjunction reading is not available. Using conjunction reduction on (52) and (53) we get:  John and Jane moved a piano and met for lunch.   (54) has a reading on which ‘moved the piano’ is interpreted distributively (two liftings) and ‘met’ is read collectively. The felicity of the conjunction reduced (54) suggests that the ambiguity isn’t the result of an ambiguity in conjunction. (see Schein (2006), McKay (2006)). We can try to use the test in an extended manner on full sentences if we embed them under ‘says that’ or perhaps ‘believes that’: ‘John and Adam believe that Sarah bought a superfluous hair remover’ is infelicitous if the unconjoined sentences involve different interpretations of ‘superfluous hair remover’.  The test has certain weaknesses. In actual utterances, intonation can be used to indicate an assertion or an each question (‘Ben wanted to eat that?) conjoined with ‘Ben wanted to eat that’ yields an infelicity even if the demonstrative has the same value on both occasions – though we may try to fix things up by demanding that the test be run using common intonation (at least in spoken uses of the test!). On that note, the test will judge demonstrative and indexicals to be ambiguous since they are famously not generally conjunction reducible. Similar worries concern polysemy and ambiguity, which conjunction reduction may be overly sensitive to (See Viebahn (2016) for relevant considerations). 4.2 Ellipsis  Ellipsis tests work in a manner similar to conjunction reduction tests. For example:  I saw his duck and swallow under the table and I saw hers too. (Zwicky and Sadock 1975)   (55) can mean that I saw their birds under the table or that I saw their activities of ducking and swallowing but it can’t mean that I saw one’s birds and the other’s activities. Similar features hold for structural ambiguities:  I’m happy that every man met two women and Jim is too.   It isn’t possible to interpret (56) as having ‘every man’ with wide scope in one but narrow in the other. This suggests a real ambiguity in the scope of the two quantifiers. This test has led people some philosophers to surprising results. For example, Atlas (1989) argues that the acceptability of the following suggest that negation does not interact scopally with descriptions in the ways we have come to expect:  John thinks that the King of France is not bald and Bob thinks so too.   The purported availability of both readings suggests that sentences with negation(s) and descriptions are sense-general rather than ambiguous, contradicting many standard assumptions about the available truth conditions these structures should make available. Alternatively, it may lead us to think that there weren’t as many readings as we initially thought there were (or that we have the wrong theory of descriptions). 4.3 Contradiction Tests  Another way to test for ambiguity is to test for lack of contradiction in sentences that look to be contradictory. For example, say someone argued that ‘aunt’ was ambiguous on account of not specifying maternal from paternal aunt. If that was the case, we would expect that we can access the two distinct senses of ‘aunt’ just as we can for ‘bank’. However, compare:  That bank isn’t a bank. *She is an aunt but she isn’t an aunt.   Both sentences are rather awkward but only one is doomed to life as a contradiction. This is good evidence that ‘aunt’ is unspecified with respect to which side of the family she comes from, but not ambiguous. The tests can be used for most of the other types of ambiguity:  My superfluous hair remover is not a superfluous hair remover; (I need it!) The goose is ready to eat but it’s not ready to eat; (we need to cook it first.)   (It helps to provide a paraphrase afterwards to bring out the distinct senses). The tests can be used to detect lexical, structural and thematic ambiguity. 4.4 Definitional Tests  Aristotle offers a test for ambiguity: try to construct a definition that encompasses both meanings and posit an ambiguity only if you fail. The notion of definition here has to be taken as a heavy-weight notion: ‘bank’ is ambiguous even though you can ‘define’ it as ‘financial institution or river side’. However, we can get a reasonable grip on what Aristotle had in mind. ‘Uncle’ is not ambiguous because it has a single definition that covers both: x is an uncle iff x is the brother of y and y has a child.   The test depends partly on how strict we are about what counts as a definition. And on the assumption that there are interesting definitions to be had (see Fodor 1998). 4.5 Checking the Lexicon of Other Languages  Kripke, in his famous attack on Donnellan, suggests a few tests for ambiguity that are more conceptual in nature. In particular, he makes the following intriguing suggestion:   “Bank” is ambiguous; we would expect the ambiguity to be disambiguated by separate and unrelated words in some other languages. Why should the two separate senses be reproduced in languages unrelated to English? First, then, we can consult our linguistic intuitions, independently of any empirical investigation. Would we be surprised to find languages that used two separate words for the two alleged senses of a given word? If so, then, to that extent our linguistic intuitions are really intuitions of a unitary concept, rather than of a word that expresses two distinct and unrelated senses. Second, we can ask empirically whether languages are in fact found that contain distinct words expressing the allegedly distinct senses. If no such language is found, once again this is evidence that a unitary account of the word or phrase in question should be sought. (Kripke 1977: p. 268)   In other words, since lexical ambiguity should involve something like accidental homophony, one would expect that other languages would lexicalize these meanings differently. Thus, it would not surprise one to find out that the two meanings of ‘bat’ were expressed by two different words in other languages. It may well surprise one to find out that every action verb was lexicalized as two different verbs, one for a reading on which the action was done intentionally, one on which it wasn’t in some other language.  One may worry about this test, especially with respect to its ability to differentiating sense generality from ambiguity. It would not be surprising to find out that other languages lexicalize ‘uncle’ in two different words (in Croatian, there is no one word translation of ‘uncle’: ‘stric’ means brother of one’s father and ‘ujak’ means an uncle from the mother’s side). Nonetheless, there is no reason to think that ‘uncle’ is ambiguous in English. Why wouldn’t language users create words to designate the specific meanings that are left sense-general in a different language? 4.6 Problems for the Tests 4.6.1 Privative Opposites  Zwicky and Sadock (1975) argue that sometimes the two (or more) putative meanings of a word are related by overlapping except with respect to one or more features. The Random House Dictionary, for example, gives (amongst many others) the following two definitions for ‘dog’:  any carnivore of the dog family Canidae, having prominent canine teeth and, in the wild state, a long and slender muzzle, a deep-chested muscular body, a bushy tail, and large, erect ears. Compare canid. the male of such an animal.   Ignoring for now whether or not dictionaries manage to report analyticities (is having a bushy tail really an analytic necessary condition for being a dog?), it looks like sense (ii) and (iii) differ merely by specification of gender, and so if this makes for ambiguity, it may well be hard to test for. Similarly for verbs that allow a factive and non-factive reading such as ‘report’ where the factive reading entails the non-factive. If I say ‘the police reported that the criminal was apprehended but the police didn’t report that the criminal was apprehended’ there is at least one reading that is anomalous, but largely out of contradiction engendered by entailment rather than univocality: it takes subtle intuitions to train one’s ear to hear ambiguities when the meanings are largely overlapping. As mentioned above, Pietroski and Hornstein (2002) make a similar point regarding syntactic ambiguities. Noting that the two putative readings of ‘every man loves a woman’ are such that the wide scope ‘a woman’ reading entails the narrow, they ask whether or not we should be countenancing a structural ambiguity or chalking up the two ‘readings’ to confusion over the specific and general case. If these sorts of factors can interfere, we will indeed have to apply our tests gingerly. 4.6.2 The Inconsistency of Zeugma  A problem for the conjunction reduction test involves the context-sensitivity of zeugma. As noted by Lewandowska-Tomaszczyk (following Cruse 1986), the following two are different in terms of zeugma:  ?Judy’s dissertation is thought provoking and yellowed with age. Judy’s dissertation is still thought provoking although yellowed with age.   Similarly, from the literature on generics:  Bees thrive in warm environments and hence are swarming my porch.   These cases looks like a problem for the conjunction reduction test, depending on how one thinks we should treat the ambiguity in generics. One might think that this provides evidence against ambiguity in bare plurals. 4.7 Contextual Resolution and Degree of Zeugma  As we suggested above, context-sensitivity, vagueness and indexicality are frequently thought to be different phenomena than ambiguity, requiring a different treatment than lexical proliferation or differences in structure. However, in context, it can be pretty easy to make them pass some of the tests for ambiguity. For example, consider James, who wants to meet a man who is is tall for a philosopher, and Jane who wants to meet a man who is tall for a horse jockey (who tend to be a fair bit shorter on average). Let’s conjunction reduce and see what happens:  ?James and Jane want to meet a tall man.   Admittedly, (65) strikes me as meriting a ‘?’ rather than a ‘#’, but I am unwilling to let it escape unmarked. Let’s try another case.  Consider, James speaking to Jill and disagreeing over the relevant height required to be tall:  ?That mani is tall but hei’s not tall.   It’s possible, I think, to get a non-contradictory reading of (66). But it requires, to my ear, adding a good helping of focal stress on the second ‘tall’. Of course, putting focal stress on a word has semantic effects of its own. So we don’t have clear counter-examples to the tests here. But we do have some evidence that running the tests requires controlling for variables.  Similarly, speaker’s reference and semantic reference distinctions mentioned above can interfere with the proper operation of the tests. Let’s consider a variant on Kripke’s famous case. We see someone who looks like Smith (but is Jones) raking the leaves and someone else sees Smith (the actual Smith) raking leaves. Can we hear the following as non-zeugmatic?  We saw Smith raking the leaves and he did too.   In context, this sounds awfully bad to me. It doesn’t seem, however, that the word ‘Smith’ is ambiguous in sometimes referring to Jones, sometimes Smith. The utterance of the word ‘Smith’ however, may well be used with referential intentions that lead to utterance ambiguity.   The bottom line is that in clear cases, the tests work great. In controversial cases, one must be very careful and run many of them and hope for the best; it will sometimes involve sifting through degrees of zeugma rather than triumphantly producing an indisputable result. 4.8 Metaphor and Non-Literal Usage  Metaphor and non-literal usage can also confound the tests. For example:  #We saw Zoe down in the dumps and her therapist did too. #Life and the 401 are highways.   The metaphors aren’t very good and (68) and (69) are clearly zeugmatic. Given how many parts of speech can be used metaphorically, slavish obedience to the test would postulate massive and unconstrained ambiguity in natural language. (See Camp 2006) The natural answer is to restrict the use of the test to cases in which the words are used literally; but of course the tests are supposed to help us decide when we have literal, semantic difference and when we don’t. To add to the complication, metaphors that are used in similar manners over time tend to become ‘dead’ metaphors – literally ambiguities that took a causal path through metaphor. ‘Deadline’ is a pretty clear case of a metaphor that has died. Since the passing of the non-literal into the standardized literal is not exactly a transition whose time of occurrence is obvious, it will be difficult in some cases to tell what has been lexicalized as a different meaning and what has not (think, again, of ‘deadline’ as a case, which once meant a line the crossing of which would result in your death. Think of that next time you are late with a paper…)  5. Philosophical Issues  There are a few main philosophical issues involved in ambiguity. 5.1 Validity  Many arguments look persuasive but fail on closer inspection on account of structural and/or lexical ambiguity. For example, consider:  Babe Ruth owned a bat. Bats have wings. Babe Ruth owned something with wings.   The argument looks valid and the premises seem true, on at least one reading, but the conclusion doesn’t follow.  If logic is to be free of issues that would complicate telling valid from non-valid arguments by form, detecting ambiguity is essential to logical representation of natural language arguments. Frege noted this to be the main defect of natural language and a real obstacle to trying to formalize it (as opposed to just using the formal language without translation from natural language). We typically are more optimistic on this point than Frege; but the long history of dispute over such issues as the pragmatic-semantics distinction and skepticism over the viability of semantic theory in general stand as challenges. 5.2 Basic Semantic Methodology  Ambiguity has been used methodologically as a way to shield a theory from counter-example. Kripke laments this tendency explicitly:   It is very much the lazy man’s approach in philosophy to posit ambiguities when in trouble. If we face a putative counterexample to our favorite philosophical thesis, it is always open to us to protest that some key term is being used in a special sense, different from its use in the thesis. We may be right, but the ease of the move should counsel a policy of caution: Do not posit an ambiguity unless you are really forced to, unless there are really compelling theoretical or intuitive grounds to suppose that an ambiguity really is present.(Kripke 1977, p.268)   Grice (1975) counsels a methodological principle: ‘Senses are not to be multiplied beyond necessity’.  This general moral seems right. It is worryingly easy to deflect a counter-example or to explain an intuition by claiming differences in meaning. On the other hand, in philosophical discourse, distinctions that are quite fine can be made that may well be missed by normal users of the language who are inclined to miss differences in meaning that are slight. One thus often will be tempted to posit ambiguity as a way to reconcile differences between two plausible hypotheses about the meanings of words and phrases (‘evidence’ has both an internal sense and an external sense, ‘right action’ has both a utilitarian sense and a deontic sense…) A neat case of this is Gilbert Ryle’s contention that ‘exists’ is ambiguous mentioned above:   …two different senses of ‘exist’, somewhat as ‘rising’ has different senses in ‘the tide is rising’, ‘hopes are rising’, and ‘the average age of death is rising’. A man would be thought to be making a poor joke who said that three things are now rising, namely the tide, hopes and the average age of death. It would be just as good or bad a joke to say that there exist prime numbers and Wednesdays and public opinions and navies; or that there exist both minds and bodies. (Ryle 1949, p. 23)   Ryle here makes use of the conjunction reduction test mentioned above and has been the target of much scorn for his intuitions on this matter. This may just go to show how hard it is to (dis)prove a claim to ambiguity using the tests. 5.3 The Analytic-Synthetic Distinction  One long-standing issue about ambiguity is that it assumes a difference between something like sense and reference. While some words can clearly be used to refer to things that are wildly different in ontic category, that has not been taken to be sufficient for a claim to ambiguity. In theory, a phrase could be ambiguous and yet differ not at all in reference: imagine a term t that was ambiguous between two meanings, but it turned out as highly surprising essential condition that things that were t in the first sense were also t in the second sense – while this seems unlikely to happen, it is by no means conceptually impossible.  However, the 20th century saw a vicious and sometimes relentless attack on the distinction between facts about meaning and facts about reference (see the entry on the    analytic/synthetic distinction).    If the line between these two is blurry, there will very likely be cases in which the line between ambiguity and sense-generality is blurry as well (and not just epistemologically). Let’s indulge in some possible-world anthropology on a group that uses a term, ‘gavagai’ (Quine 1960). Furthermore, I stipulate (perhaps counter-possibly) that the world is a four-dimensional world with respect to the referent of ‘gavagai’ so if they refer at all with ‘gavagai’, they refer to something made up of stages. Now we sit down to write the lexicon of the world’s inhabitants and we come to ‘gavagai’. We write:   ‘Gavagai’ (ga-vuh-guy): (N, sing.):   It’s not easy to know what to write down for this entry as it’s not obvious what counts as semantic content for the word and what counts as information about the referent of the word. For example, say they clearly think that the referent of ‘gavagai’ is something that does not have temporal parts. Does this mean that they fail to refer to rabbits with ‘gavagai’ or that they are mistaken about their nature? If this question is hard to answer, we can generalize to harder cases: say that some of the ‘rabbits’ in this world are three-dimensional and some four- dimensional. Should we countenance an ambiguity in ‘gavagai’ given that the people use it indiscriminately to refer to both? Should we posit a lexical ambiguity with two different definitions for ‘gavagai’?  This case may be far-fetched; but we have a real live cases of it. Field (1973) discusses the case of the term ‘mass’, which seems to have been thought to pick out one property of objects but in fact picks out two that are really very different in character. Deciding whether this is a surprising case of disjunctive reference, or an indeterminacy in reference is no easy task, but the decision has ramifications for whether or not we categorize ‘mass’ as ambiguous or highly sense-general (and if sense-general, what is the general sense?) 5.4 The Flexibility of the Lexicon  The lexicon is highly productive and easily extended. Most people, including myself, upon hearing:  She bought a rabbit.   will think that it’s safe to infer that she bought a fuzzy little pet that hops around and likes carrots. However, upon learning that there is a car by the same name made by Volkswagen, it will be much less clear to me that I know what she bought.  Similar phenomena include dead metaphors and idioms. The former include such items as ‘branch’ which now applies to distinct sections of the government, the latter to phrases ‘kick the bucket.’ (As an aside, I puzzled over several candidates for both and realized it was hard to tell in most cases which were which!) These clearly pass the ambiguity tests above by exhibiting zeugma, i.e.,  ?The government and the trees have branches. ?He kicked the bucket last week and she did too, twice.   It’s controversial whether metaphors ever actually die and whether or not, assuming they do die, they are metaphors. So it is controversial whether or not ‘branch’ is lexically ambiguous. It clearly has two readings but whether or not these are to be reflected as lexical meanings is a difficult and vague matter – not that it clearly matters all that much in most cases. 5.5 Legal Interpretations  On the other hand, the facts about ambiguity can matter a great deal when it comes to determining policy, extension of law etc. The law is sensitive to this and makes certain division between ambiguities. For example, the law divides between patent and latent ambiguity, where the former roughly corresponds to a case where the meaning of a law is unclear, the latter to cases where the meaning is clear but applies equally well to highly disparate things. In effect, this is the difference between ambiguity in sense and ambiguity in reference.  U.S. Constitution scholars sometimes claim that the Constitution is ‘ambiguous’ at key points. A famous example of such an ambiguity is the succession of the vice president, where the framers stipulate that:   In Case of the Removal of the President from Office, or of his Death, Resignation, or Inability to discharge the Powers and Duties of the said Office, the same shall devolve on the Vice President, (Article 2, section 1)   The clause is not clear as to what ‘devolve’ means.  Of course, given what has been discussed, this looks to be more like a case of under-specificity, or simply ignorance of a word’s meaning (in 1787), not ambiguity. As the distinction has no real legal relevance in this case, it is ignored as it generally is in common parlance. 6. Ambiguity and Indexicality: Are They Easily Told Apart?  In  section 2  we looked at phenomena that were not the same as ambiguity; in this section, we look at a few cases in which we might have been wrong to tear them apart. 6.1 Deictic vs. Bound Anaphora  It is often claimed that:  John loves his mother.   is ambiguous between a deictic reading and a bound reading. Syntactic orthodoxy holds that either ‘his’ is co-indexed with John or it bears a different referential index. Various theories of anaphora, however, have claimed that we can dispense with the fundamental ambiguity between free and bound anaphora and unify the treatment of the two. Dynamic Semantics aspires to offer just such a unified account, taking all anaphora to always refer to discourse referents, or functions from information states to information states. This provides a unified treatment of the function of anaphora in natural language and dispenses with the need to think of anaphoric interpretation as ambiguous as opposed to merely context-sensitive. (See Heim 1982, 1983, and Kamp 1981). 6.2 The Scope of Indefinites  Consider:  Every man who read a book by Chomsky is happy.   (77) is ambiguous between one where ‘a book by Chomsky’ takes wide scope over ‘every man who reads’ and one where it takes narrow scope. Maybe so; but most quantifiers in fact cannot escape from relative clauses. Relative clauses are known as ‘scope islands’, or contexts in which quantifiers can’t be interpreted as raised. In fact, it has been noted that indefinites seem to escape from nearly any normal scope island whatsoever. This suggests that treating the various readings as an ambiguity akin to other scopal ambiguities is mistaken. Another treatment of (77)’s multiplicity of readings involves domain restriction: if we restrict the domain of ‘a book’ to only one particular book, we can emulate the reading one would get from treating ‘a book’ as having wide-scope. Domain restriction traditionally is treated as a matter of context sensitivity rather than ambiguity. We thus have some reason to doubt that the right treatment of (77) has much to do with the phenomenon of scope. (see Schwarzchild (2002) for further discussion). 6.3 Modals  As noted above, modals seem to come in various flavours (doxastic, metaphysical, logical, deontic, practical…). It is tempting to treat these as ambiguities involving the modal term. However, it is worth noting that other treatments abound. Kratzer (1983) treats modals as univocal but indexical: they get their differing interpretations by taking in different input sets of worlds and orderings induced on the relevant sets. If this is right, it may well be that what looks like an ambiguity should actually be treated as a matter of straightforward indexicality (much like ‘I’ is not ambiguous but indexical). 6.4 Focal Stress A really interesting case that may be loosely described as ambiguity at the level of a sentence concerns focal stress and its myriad of interesting effects. Generally focal stress is well known to co-ordinate assertions with questions under discuss and to introduce sets of alternatives into a discourse. In particular, these alternative sets can have truth conditional effects, for example:  Putin only poisons his opponents. Putin only poisons his opponents  (78) is falsified by Putin shooting an opponent, (79) is not. (78) introduces a presupposition that Putin does something to his opponents while (79) introduces a presupposition that Putin poisons someone. The sentence, thought of in terms of orthography, ‘Putin only poisons his opponents’ is thus ambiguous. Assuming that focal stress is syntactically marked, the LF disambiguates. See (Rooth (1993) and Herburger (2000) for semantic theories of focal stress).  6.5 Cancellation vs. Disambiguation  Griceans have long used cancellation as a method to detect conversational implicatures, or information communicated by an utterer of a sentence that isn’t part of what’s said by S. Cancellation is a procedure by which an explicit denial of putatively conveyed information is conjoined to the original utterance to see if the result is a contradiction. For example, consider an utterance of:  I got drunk and I drove home (but not in that order).    The non-bracketed sentence, absent an utterance of the bracketed content, will typically convey the order events as being mirrored in the order of the conjuncts. But, as Grice famously argued, this isn’t due to an embedded ordering in the meaning of ‘and’ as shown by the addition of the bracketed content not producing a contradiction. The Gricean stories about how we come about this extra information in non-cancellation cases is fairly well known. But given the preceding, it’s not hard to see that an option has been overlooked: why shouldn’t we think of ‘but’ as playing the role of a disambiguator? If ‘and’ were ambiguous, for example, wouldn’t one way of avoiding an contradictory utterance involve adding a phrase that ruled out one possible meaning? We saw Grice’s claims about Modified Occam’s razor and so perhaps attributing an ambiguity to ‘and’ is not so attractive.  But perhaps an ambiguity in the assignment of times to the present tense markers is, and the putative cancellation serves to indicate the intended resolution of the those variables? Or perhaps ‘and’ signals two or more possible discourse relations and the putative cancellation services to disambiguate between those? Lepore and Stone (2016) put disambiguation to work in an attempt to show that ambiguities in interpretation are more rife and wide spread than we might have previously assumed. If they are right, ambiguity plays a more central role than perhaps might have been thought in sentence, utterance and discourse interpretation. It remains to see if they are. The point of these examples is that it is often difficult to tell which theoretical treatment best explains a case of multiple interpretability. One must be cautious in one’s approach to these issues. It is all too easy to notice an apparent ambiguity, but often all too difficult to explain its nature. 