the defendants who meet all the character- istics (e.g., both 20-25 years old, interracial couple, yellow Dodge hardtop with bent fender) observed by bystanders ...
Journal of Experimental Psychology: General VOL. 107, No. 1
MARCH 1978
Psychology of Pragmatic Implication: Information Processing Between the Lines Richard J. Harris and Gregory E. Monaco Kansas State University SUMMARY This article looks in depth at an often neglected aspect of human communication—its probabilistic nature, which frequently is reflected in semantic misinterpretations of the language-producer's message by the language comprehender. The former does not always know whether his message is being interpreted correctly and the latter often "misinterprets" the message. It is this fact that makes human communication probabilistic. In fact, language comprehension may be viewed as an ongoing process of continual hypothesis testing. In a review of the psycholinguistic, linguistic, and philosophical literature dealing with this aspect of language, we demonstrate that such misinterpretation of the speaker's message due to the probabilistic nature of language is in fact related to a basic process of the hearer's information-processing system: storage of meaningful information that is either directly asserted by the speaker or inferred by the hearer. Although stored information that has been directly asserted is not a contributing factor to probabilistic communication, stored information inferred by the hearer is. Inferences that follow logically and necessarily from the speaker's directly asserted message are logical inferences. Pragmatic implications occur when utterances of the speaker strongly suggest (rather than directly assert or logically imply) another piece of information and may lead the hearer to make a pragmatic inference. Recent research has demonstrated in a wide variety of tasks, including specific applications to courtroom testimony and commercial advertising, that information that has been pragmatically inferred is recalled and recognized as if it had been directly asserted. This evidence is used to argue against performance theories that do not take the probabilistic nature of communication into account and to support a construction hypothesis that emphasizes the storage rather than the retrieval process as the locus of inference construction. Directions for further research using the concept of pragmatic implication as both a method and a diagnostic tool are proposed.
Copyright 1978 by the American Psychological Association, Inc. All rights of reproduction in any form reserved. 1
RICHARD J. HARRIS AND GREGORY E. MONACO
It has frequently been noted in the linguistic, philosophical, and psycholinguistic literature that a language comprehencler may not always correctly comprehend a language-producer's intended message. Such misinterpretation and misunderstanding vary from subtle nuances of meaning to a complete distortion of the intended message. Although serious verbal miscommunication may occur relatively seldom, very frequently the hearer comprehends or remembers something other than precisely what the speaker intended. This is because language comprehension involves a continual hypothesis testing that constructs semantic interpretations based on the linguistic and nonlinguistic context, as directed by the hearer's world knowledge. As Frederiksen (1975) says, Understanding, then, may be regarded as a process whereby a listener or reader attempts to infer the knowledge structure of a speaker or writer by using the available linguistic message, contextual information, and his own knowledge store as "data structures" from which the inference is to be made, (p, 371)
Such constructed semantic hypotheses vary from substantially correct to totally incorrect. No psycholinguistic theory has adequately dealt with this issue of the probabilistic nature of language. It is probabilistic in that the speaker does not always know if his message is being interpreted as he wishes and because the hearer does not always know if he is correctly interpreting the message. This article examines aspects of language that reflect this probabilistic process, focusing on those aspects that may be conceptually unified under the heading of pragmatic implication. This work was supported by grants to the first author from the Kansas State University Faculty Research Award Committee. Appreciation is expressed to Janice Keenan, Elizabeth Loftus, Kristin Bruno, Charles Osgood, William Brewer, Marc Rosenberg, Baruch Fischhoff, Faith Hall, and Ross Teskc for helpful comments on previous drafts of the manuscript. Requests for reprints should be sent to Richard J. Harris, Department of Psychology, Anderson Hall, Kansas State University, Manhattan, Kansas 66506.
Pragmatic Concept
Implication:
Genesis
of the
An implication is a type of meaning carried in an utterance (or sentence) but which must be derived by logic or heuristics from the utterance itself. This is in contrast to the directly asserted meaning of the utterance. Both asserted and. implied meanings make up what is considered the semantic content (message) of the communication. Brewer (Note 1) has distinguished between two kinds of implications carried in sentences. A logical implication exists when some information is necessarily implied by an utterance. For example, la. John forced Bill to rob the bank.
logically implies that lb. Bill robbed the bank.
In the same way Sentences 2a, 3a, and 4a logically imply Sentences 2b, 3b, and 4b, respectively. 2a. 2b. 3a. 3b. 4a. 4b.
Kathy is taller than Mary. Mary is shorter than Kathy. George managed to cut the grass. George cut the grass. All collies are dogs. Lassie, a collie, is a dog.
There is no way to interpret Sentences la, 2a, 3a, or 4a meaningfully in English without believing the corresponding logical implication to be true. 1 On the other hand, a pragmatic implication exists when an utterance "leads the hearer to expect something neither cxplic1
It is possible to further subdivide Brewer's (Note 1) category of logical implication. For example, Austin (1962) distinguishes between eutailmcnt (if p entails q, then ~/> entails ~r/) and implication (if p implies q, ~£ need not imply ~g). Also, a logical implication may invariably follow from a single word, for example, bachelor implying not married (often called semantic entailment) or from a combination of words, e.g., Sentences 1-4. Logical implication, as used here, is thus more general than the highly specific material implication used in symbolic logic (e.g., Kahane, 1969) to refer to the particular relation of a p —> q (conditional) rule, which is consistent with pi], ~pq, and ~£ ~^, and is discontinued only by p ~y. Since logical implication is not the major concern of this article, such distinctions will not be considered further.
PSYCHOLOGY OF PRAGMATIC IMPLICATION
itly stated nor necessarily (logically) implied" (Brewer, Note 1, p. 4) in the sentence. For example,
denial. Consider, for example, the incongruence or unexpectedness (but not contradiction) of the following:
5a. The karate champion hit the cement block.
12. The karate champion hit the cement block, but he did not break it. 13. The fugitive was able to leave the country, but he did not.
pragmatically implies that Sb. The karate champion broke the cement block.
In the same way, Sentence 6a pragmatically implies Sentence 6b, and Sentence 7a pragmatically implies Sentence 7b. 6a. The fugitive was able to leave the country. 6b. The fugitive left the country. 7a. The absent-minded professor didn't have his car keys. 7b. The absent-minded professor lost (or forgot) his car keys.
Unlike logical implications, however, pragmatic implications do not have to be understood to meaningfully comprehend a sentence. Thus, in some contexts, it is perfectly reasonable that a karate champion might hit a cement block but not break it or that a fugitive might be able to leave the country but choose not to do so. It is true, however, that, without any indication to the contrary from the context, a hearer is usually led to make the pragmatic inference on hearing such a sentence.2 The notion of pragmatic versus logical implication conceptually unifies under one heading different labels used in psychology, linguistics, and philosophy for this phenomenon that occurs in different semantic, syntactic, and contextual domains. It accounts for Osgood's (Note 2) distinction between contradiction and incongruence. Contradiction would result from two statements or events that positively could not hold at the same time, such as the following logical implications and their denials: 8. *John forced Bill to rob the bank, but Bill refused. 9. *A11 collies are dogs, but Lassie, a collie, is not a dog. 10, *Joe is a bachelor, but he is married. 11. "Kathy is taller than Mary, but Mary is not shorter than Kathy.
However, incongruence rather than contradiction would result from two statements or events that could conceivably hold at the same time but most likely would not, that is, a pragmatic implication and its
The logical-pragmatic implication distinction has long been noted by at least a few philosophers. For example, Bar-Hillel (1946) said that A "pragmatically induces" B, if and only if there exists a highly confirmed sentence class S of pragmatic laws such that A implies B relative to S. Hungerland (1960) defines a "contextual implication" as that which a speaker believes as a result of hearing an utterance but which is "neither asserted by the speaker nor is it entailed (logically implied) by anything he asserts" (p. 211). NowellSmith (1954) says that "p contextually implies q if anyone who knew the normal conventions of the language would be entitled to infer q from p in the context in which they occur" (pp. 80-81). He defines logical implications as the subset of contextual implications that hold in all contexts. The psychologist Singer (1976) also uses the term context inferences, defined as "a function of the interactions among the meanings of the lexical elements within a sentence . . . strongly suggested but not logically implied by the sentences from which they are derived" (p. 40). Black (1962) distinguished between two kinds of implication and discussed pragmatic implication at some length. The contrast is developed between pragmatic implication (hinting, insinuating, suggesting, etc.) and assertion (saying outright, saying in so many words, etc.). Both are part of the speaker's whole communication or message, but the implication is usually in a position of subordination, or lesser focus, relative to the assertion. This relation a The traditional dictionary distinction between implication and inference is followed here. A speaker, sentence, or utterance makes an implication; a hearer or reader makes an inference. The logicalpragmatic distinction is appropriate with either term.
RICHARD J. HARRIS AND GREGORY E. MONACO may be reversed, however, as 14a. Gee, it's cold in here.
may be used to request the hearer to close the window, thus making the pragmatic implication 14b. Please close the window.
ence in our stored knowledge about pythons and dogs. 18a. The hungry dog caught the mouse. 18b. The hungry dog ate the mouse.
Similarly, pragmatic implication may involve an implied cause. One hears an utterance reporting an event, that is,
the primary communicative focus of the 19a. The clumsy chemist had acid on his coat. utterance (e.g., Grice, 1975). Certain psychologists and linguists have and then pragmatically infers a probable offered definitions of implication that, if not cause for that event, that is, quite pragmatic, at least tend in that direc- 19b. The clumsy chemist spilled acid on his coat. tion. For example, Kintsch (1974) says that "p implies q if and only if given a semantic Although the cause is only probable, such memory 5 which contains a set of inference inferred causes can be very strong pragrules /, and a given proposition p, q is matic implications, for example, see also derivable from p" (p. 57). Karttunen Sentences 7a and 7b. Pragmatic implication may also involve (1971) says that "p implies q means only the implied instrument of a stated action, that asserting p commits the speaker to q" ; as noted by Johnson, Bransford, and whereas the next year, Karttunen (1972) Solomon (1973) and Paris and Lindauer weakened the definition to "p implies q if (1976). On hearing Sentences 20a, 21a, or and only if whenever p is asserted, the 22a, one might infer Sentences 20b, 21b, or speaker ought to believe that q" (p. 6). 22b, respectively, although the latter three Although the logical-pragmatic distinction would not necessarily have to be true. has seldom been made explicit, this distinction can have important empirical and 20a. John was pounding the nail to fix the birdhouse. 20b. John was using a hammer to fix the birdhouse. theoretical consequences. 21a. John stuck the wallpaper on the wall. As one example, pragmatic implication 21b. John pasted the wallpaper on the wall. may involve events in a temporal sequence. 22a. The truck driver stirred the coffee. If one hears 22b. The truck driver stirred the coffee with a spoon. 15a. The safccracker put the match to the fuse, Interestingly enough, there may be some implied-instrument sentences in which the one might likely infer that implication is logical rather than pragmatic, 15b. The safecracker lit the fuse. for example, was true, although such an implication is 23a. John chewed his T-bone steak. not logically necessary. Because of our 23b. "John chewed his T-bonc steak but not with teeth. knowledge of the world, we have come to his 24a. The quarterback kicked the football. expect that certain events such as Sen- 24b. *The quarterback kicked the football but not tences 15b, 16b, and 17b will follow certain with his foot. other events such as Sentences 15a, 16a, as the contradiction resulting from the and I7a most of the time. denial of the implication illustrates (Sen16a. The hungry python caught the mouse. tences 23b and 24b). In such sentences as 16b. The hungry python ate the mouse. 23 and 24, mentioning the obvious instru17a. The man dropped the delicate glass pitcher. ment seems highly redundant, since ap17b. The man broke the delicate glass pitcher. parently the possibility of any other instruSuch expectations may sometimes be very ment is nil. Still another example of pragmatic imstrong, although a very similar pair of sentences would not carry the same relation, plication involves implied location. Because for example, Sentence 18a, would seldom of one's knowledge of the world, certain imply Sentence 18b, because of the differ- events typically occur in certain places, al-
PSYCHOLOGY OF PRAGMATIC IMPLICATION though not necessarily so. For example,
directly so stated. Thus,
25a. The paratrooper jumped out of the door. 26a. The barnacles clung to the sides.
3 la. The dock workers talked about their high taxes,
may pragmatically imply that 25b. The paratrooper jumped out of the plane. 26b. The barnacles clung to the ship.
although other locations are also logically possible, for example, 25c. The paratrooper jumped out of the practice apparatus. 26c. The barnacles clung to the pier.
Antony mous adjectives also show a logical-pragmatic difference in implication. Dichotomous antonyms (e.g., male-female, dead-alive, equal-unequal), when negated, logically imply their opposite. However, continuous antonyms (e.g., hot-cold, tallshort, weak-strong), when negated, only pragmatically imply their opposite, that is, there is here available a choice of the middle of the continuum, with the label for neither end being appropriate. Thus, 27. *Joe was not dead, but he was not alive, is contradictory, whereas 28. Joe was not tall, but he was not short.
is at worst incongrucnt. Austin (1962) and Schwellcr, Brewer, and Dahl (1976) discuss illocutionary and perlocutionary acts performed in making utterances. An illocutionary act is the performance of an act in saying something, that is, the utterance itself is the act it describes, as in 29. He urged (advised, ordered, etc.) me to shoot her.
A perlocutionary act is the performance of an act that produces certain consequential effects on the feelings, thoughts, or actions of the hearer as in 30. He persuaded me to shoot her.
It is possible that an utterance may not be overtly illocutionary, but may often function similarly, that is, it may have what Austin (1962) calls "illocutionary force." For example, the act of talking about high taxes in Sentence 3la may have the illocutionary force of a complaint, although not
may be said to pragmatically imply that 31b. The dock workers complained about their high taxes.
Similarly, a perlocution may carry a pragmatic implication, for example, Sentence 32a implying Sentence 32b: 32a. The teaching assistant told the psychology class that there would be no final exam. 32b. The teaching assistant's announcement delighted the psychology class.
In certain contexts, even a very neutral and apparently uninformative answer to a question can carry a moderately strong pragmatic implication. Consider, for example, certain types of questions of the sort frequently asked of politicians, showbusiness personalities, and others in the public eye: 33. Are you and your husband contemplating separation ? 34. Did you have any knowledge that men under you were planning illegal covert operations?
The frequent response of "no comment" to such a questions may carry a pragmatic implication of "yes." Questions themselves can carry strongpragmatic implications of their answers, such as by the addition of negation in a yes-no question, thus implying the speaker's belief in an affirmative answer, for example, 35. Didn't you come into class late?
One example of pragmatic implication discussed at some length under different names in the linguistic literature involves interpretations of conditional statements. Following Geis and Zwicky (1971), this type of pragmatic implication has been called an invited inference. Geis and Zwicky pointed out that a sentence like 36. If you mow the lawn, I'll give you five dollars.
carries the invited inference (pragmatic implication) that if the hearer does not mow the lawn, he will not get five dollars. Although Geis and Zwicky have been criticized for claiming that an invited inference
RICHARD J. HARRIS AND GREGORY E. MONACO
is a necessary part of such sentences lin- only pragmatically implies that guistically rather than merely a reflection 38b. John did not go to Timbuktu, of one's knowledge about the world (Boer & Lycan, 1973; Lilje, 1972), clearly such and a pragmatic inference is often made from 38c. John was not forced to go to Timbuktu, but he such statements in many contexts. went there (anyway). Philosophers dealing with prepositional logic have also considered conditional sen- is perfectly acceptable. See Karttunen tences at length, usually considering them (1971, 1972) or Harris (1974a) for a more to follow the truth-table rule of "material complete discussion of If verbs, as well as implication" (e.g., Kahane, 1969). This has similar classes of Negative If (e.g., prevent, often been referred to simply as "implica- keep from) and Only If (e.g., be able, have tion," thus further proliferating the con- the chance) verbs. Although many other examples of pragfusion around the use of this term. In matic implications of utterances could be terms of logical and pragmatic implication cited, the above serve to adequately illusas defined in the present article, given a conditional statement, for example, Sen- trate the phenomenon. The following sectence 36 and p (hearer mows the lawn), q tions demonstrate how these members of (hearer gets five dollars) is logically im- such a seemingly disparate category have plied. However, given the conditional state- similar psychological properties and thus ment and not p (hearer does not mow the belong to a single class of psychological lawn), not g (hearer does not get five phenomena. dollars) may be pragmatically implied, but it is certainly not logically implied. In fact, Pragmatic Implication in Psycholinguistics in an exhaustive review of the psychological In an early but remarkably modern study reasoning literature, Wason and Johnsonof memory for prose by children, Binet and Laird (1972) concluded that it is the meanHenri (1894) noted several types of recall ing and the individual's rules of inference shifts. One, called "errors by imagination," that arc involved in the deductive compoincluded distortions of meaning in a variety nent of one's thought, rather than solely of ways. Some of Binet and Henri's exthe logical forms of premises and axioms. amples, for example, Sentence 39a recalled Certain sentence-complement verbs as Sentence 39b, are clearly pragmatic whose meaning may be described in part inferences: by a conditional rule often carry such pragmatic implications about the truth 39a. Le petit Emiie a obtenu un cheval mdcanique. value of their sentential complements (Little Emile got a mechanical horse.) (Karttunen, 1970, 1971, 1972). For ex- 39b. On lui a achete un cheval mecanique. (Someone ample, the class of If verbs (e.g., cause, bought him a mechanical horse.) force, compel) carries a logical implication Many of the recall shifts noted by if affirmative, but only a pragmatic impli- Bartlett (1932) in his studies of memory cation if negative. Thus, for prose passages could be considered pragmatic implications. For example, 37a. John was forced to go to Timbuktu. logically implies that
40a. That Indian has been hit.
37b. John went to Timbuktu.
was recalled as
as evidenced by the contradiction
40b. lie had been wounded by an arrow.
37c. "John was forced to go to Timbuktu, but he didn't go there.
Bartlett notes that the subjects' knowledge and beliefs about the material they had read were reflected in their recall protocols. Bartlett's notion of construction will be discussed in detail later.
However, 38a. John was not forced to go to Timbuktu.
PSYCHOLOGY OF PRAGMATIC IMPLICATION
Several recent studies, using a variety of tasks, have demonstrated that subjects are very likely to remember a pragmatic implication of an utterance rather than the utterance itself or what it directly asserts or logically implies. For example, Brewer (Note 1) presented subjects with lists of sentences such as 41a, 42a, and 43a in a cued-recall task. Subjects more frequently (26% of total responses) recalled the pragmatic implications of the sentences, for example, 41b, 42b, and 43b, than what they had actually heard (19% of total responses). 41a. The angry rioter threw a rock at the window. 41b. The angry rioter threw a rock through the window. 42a. The hungry python caught the mouse. 42b. The hungry python ate the mouse. 43a. Dennis the Menace sat in Santa's chair and asked for an elephant. 43b. Dennis the Menace sat in Santa's lap and asked for an elephant.
In a cued-recall study of sentences containing dichotomous and continuous antonyms, Brewer and Lichtenstein (1975) found that subjects recalled, for example, not hard as soft equally as often as they recalled not equal as unequal, although the first shift reflects only a pragmatic inference, whereas the second shift reflects a logical inference. Johnson et al. (1973) used a recognition memory task to study the same problem. Subjects hearing sentences like 44a and 45a embedded in a brief story were more likely to falsely recognize a similar sentence containing a pragmatic implication of the presented sentence, for example, Sentences 44b or 45b, than a control sentence equally related semantically to the input sentence but not implied by it. 44a. 44b. 4Sa. 45b.
(Someone) dropped the delicate glass pitcher. (Someone) broke the delicate glass pitcher. He was pounding the nail. He was using the hammer.
Schweller et al. (1976) found that memory shifts in a cued-recall memory task were consistent with the illocutionary force pragmatically implied by the input sentence. For example, subjects hearing Sentence 46a more often recalled Sentence 46b than those hearing Sentence 47a recalled
Sentence 47b. Thus, apparently subjects made the pragmatic inference that Sentence 46a was spoken as a complaint. 46a. The housewife spoke to the manager about the increased meat prices. 4Va. The housewife spoke to the manager about the upcoming baseball game. 46b. The housewife complained to the manager about the increased meat prices. 47b. The housewife complained to the manager about the upcoming baseball game.
Similarly, Schweller ct al. found that subjects falsely recognized a pragmatically implied perlocution of an utterance. For example, Input Sentence 48a was often falsely recognized as Sentence 48b but not as Sentence 48c. 48a. The English professor told his students a dull story about Jane Austen. 48b. The English professor bored his students with a story about Jane Austen. 48c. The English professor amused his students with a story about Jane Austen,
In a study of the comprehension and memory of complex verbal-complement sentences using verbs containing a conditional rule as part of their meaning, Harris (1974a) had subjects listen to lists of sentences such as 49a and 50a. One group of subjects was asked, after hearing the list, to judge sentences such as 49b and 50b as true, false, or of indeterminate truth value, where Sentence 49a pragmatically implies Sentence 49b, and Sentence 50a pragmatically implies Sentence 50b. 49a. The frightened farmer was able to raise chickens. 49b. The frightened farmer raised chickens. 50a. Miss America was not prevented from playing the tuba. 50b. Miss America played the tuba.
In this memory task, statements either pragmatically or logically implied were judged true most of the time. A different group of subjects, judging the same implied sentences as true, false, or of indeterminate truth value immediately after hearing each stimulus sentence (instead of as a memory task), correctly judged significantly more of the pragmatic implication sentences as of indeterminate truth value. This showed that subjects can make such
RICHARD J. HARRIS AND GREGORY E. MONACO
logical-pragmatic distinctions in comprehension. The memory effect was replicated with a wider variety of types of pragmatic implications, using the same task but with simulated courtroom testimony (Harris, Teske, & Ginns, 1975; Harris, Note 3), mock radio commercials (Harris, in press; Bruno, Note 4), and brief stories (Bruno, Note 4; Monaco, Note 5) as stimulus materials. The evaluation of pragmatic implications as true rather than indeterminate occurred in the Harris et al. (1975) study, even after very obtrusive initial instructions warning subjects not to make such inferences and store that inferred material as fact. In studies of syllogistic reasoning (sec Wason & Johnson-Laird, 1972, for a review), considerable numbers of performance deviations from the formal logic model have been found consistently, for example, the "illicit conversion" of All X is Y to All Y is X. Such performance is readily interpretable as pragmatic implication. Chapman and Chapman (1959), for example, say that Such interpretations, although logically invalid, often correspond to our experience of reality, and being guided by experience arc usually regarded as justifiable procedures. One may realistically accept the converse of many, perhaps most, O propositions about qualities of objects, e.g., some plants are not green, and also some green things are not plants. . . . Conclusions are often reached by probabilistic inference. . . . S reasons that things that have common qualities or effects arc likely to be the same kinds of things, but things that lack common qualities or effects are not likely to be the same. . . . Such thinking is not unreasonable; rather it is the reasoning process by which most science progresses. Thus a chemist might reason as follows: "Yellow and powdery material has often been sulfur. Some of these test tubes have yellow powdery material. Therefore some of these test tubes contain sulfur." This is ... invalid . . . yet the conclusion has some probability, (pp. 224-225)
Many studies of conditional reasoning with various types of linguistic materials have demonstrated the frequent use of pragmatic inference in the comprehension of such materials. For example, in a reaction time study, Chaffin (1975) found that true-false verifications involving the logical and pragmatic inferences of complex sentences such as those used by Harris (1974)
were made equally fast. Similar results were obtained by Springston and Clark (1973), who found that subjects made pragmatic inferences to pseudoimperatives (disguised conditionals), such as 51. Flip the switch or the fan goes on.
just as fast as they made logical inferences. Taplin (1971) presented subjects with linguistic conditional arguments such as Sentences 52a, 52b, and 52c and asked them to evaluate each conclusion, for example, Sentence 52e, as true or false. In cases like 52a. If John gets elected, then he will be famous. 52b. John does not get elected. 52c. John will not be famous.
a large majority of the subjects who were logically consistent at all answered true, whereas in fact Sentence c is not a valid deduction but rather a pragmatic implication. Taplin interpreted his results as supporting subjects' use of a biconditional (if and only if), rather than a conditional (material implication), truth table in this task—logically, the same strategy used by subjects in the Harris (1974a) study and pointed out by Gcis and Zwicky (1971). Subjects make the pragmatic inference that Sentence 52a logically implies Sentence 53, that is, is describable by a biconditional (if and only if) rather than a conditional (if) rule. 53. If John does not get elected, then he will not be famous.
Taplin and Staudenmayer (1973) replicated the findings of Taplin (1971) but used abstract materials, for example, Sentences 54a, 54b, and 54c. In a second experiment, however, they allowed subjects to respond "always true," "never true," or "sometimes but not always true" (with a control group answering "false," "never false," or "sometimes false"). 54a. If A, then B. 54b. A does not occur. 54c. B does not occur.
With three response categories instead of two, many subjects answered items such as Sentences 52c and 54c as sometimes true
PSYCHOLOGY OF PRAGMATIC IMPLICATION
(or false), thus apparently using something other than the biconditional rule. Thus, apparently conditional sentences like 52a and 54a are ambiguous and may be interterprcted in accord with either a conditional or biconditional rule. In many contexts, however, it seems to be true that such a conditional statement pragmatically implies a biconditional interpretation. For example, in Geis and Zwicky's (1971) original example (Sentence 36), it does seem probable that if the hearer does not mow the grass he won't receive the five dollars, although he might still do so by doing another job instead or finding extraordinary generosity in the speaker. The fact that Taplin and Staudenmayer (1973) found such different results merely by changing from a two-category to threecategory response scale underscores the importance of the context in the interpretation of such sentences, where the strength of a pragmatic implication can be greatly affected by even rather mundane characteristics of the experiment, which may become powerful task demands. Some other variables that affect conditional reasoning are thematic presentation and nature of the task (Johnson-Laird, Legrenzi, & Legrenzi, 1972; Wason & Shapiro, 1971) and naturalness of the relation of problem elements (Bracewell & Hidi, 1974). Parallel results have been found in many studies of nonlinguistic conditional reasoning (e.g., Johnson-Laird & Wason, 1970; Wason, 1969; Wason & Johnson-Laird, 1970). In many such studies the subject is given four cards, for example, U, 3, B, 7, and a conditional rule such as Sentence 55. The subject is asked what cards would have to be turned over to verify or disconfirm that rule. 55. If there's a D on the letter side, then there's a 3 on the number side.
While the logically correct choices are D and 7, most subjects choose D and 3, that is, they interpret the rule as a biconditional "D on one side if and only if 3 on the other." However, when Johnson-Laird and Tagart (1969) gave subjects valid and invalid conclusions from such a task and allowed judgments of true, false, or irrele-
vant, most subjects did not use a biconditional rule but rather judged turning over a 3 in the above example as irrelevant to testing the rule. Thus, again there is evidence for a conditional rule statement pragmatically implying the correspondingbiconditional, but with such implication greatly reduced by slight changes in the task demands. In real-world use, clearly the context of a conditional rule greatly affects the strength of the biconditional pragmatic implication. It is clear that pragmatic inferences arc made in comprehension and memory in a wide range of tasks using linguistic materials in a variety of syntactic forms and even with nonlinguistic stimuli. It is now time to examine in detail some theoretical and methodological issues in the study of pragmatic implication. Some Critical Issues in Studying Pragmatic Implication The research on pragmatic implication began with cuecl-rccall studies (e.g., Brewer, Note 1) using lists of sentences that were sernantically unrelated to one another, and in which it was usually possible to determine whether the subject had made the pragmatic inference of interest merely by his production of one key word. For example, if the subject heard 56a. The karate champion hit the cement block.
and was presented with "the karate champion" in a cucd-recall test, it was possible to determine efficiently whether the subject had made a pragmatic inference by examining the verb produced. If the subject responded S6b. The karate champion broke the cement block.
it was assumed that a pragmatic inference had been made. In an attempt to expand the concept by examining simulated speaker-hearer communication, more recent research has studied pragmatic implications that are not only carried by one word or one sentence but also by two or more contextually related sentences. With these materials, cued
10
RICHARD J. HARRIS AND GREGORY E. MONACO
S7a. There was no porch in front of the cabin, just two chairs there to sit in on the frequently cool nights. The chairs were rustic looking and uncomfortable without pillows. They were set far apart.
cerned) as new because he did not construct one of the two pragmatic inferences. Second, some pragmatic implications are conveyed by the entire passage and not by one particular sentence. It is possible that a subject, having heard Paragraph 57a, would construct the pragmatic inference of Sentence 57b, but would identify Sentence 58 as new because he realizes that Sentence 58 has the added word log; thus, being scored incorrectly by the experimenter on number of pragmatic inferences made.
This paragraph contained the pragmatic implications that
58. There was no porch in front of the log cabin, just two chairs to sit in on the frequently cool nights.
57b. S7c. 57d. 57e.
Both of these problems make the criterion of verbatim recognition of test items wholly unsuitable. An implication or inference is not, by definition, what was "actually presented" to the subject, but rather what the subject understood. Therefore, Johnson et al.'s (1973) criterion of whether the test sentence was actually presented in the study material is not a direct test of whether the subject made the particular inference but is, instead, a measure of the subject's memory for the surface structure of the study material. Harris has developed a test that is suitable for studying implications conveyed by isolated sentences (Harris, 1974a), by contextually related sentences (Monaco, Note 5), and by connected discourse (Harris et al., 1975). This test is referred to as a recognition-of-information test and is composed of statements about the original text material, such as Sentences 57b, 57c, 57d, and 57e, with each statement followed by the alternatives true, false, and indeterminate. Although initially told only to listen to some material because questions about it would follow later, after the stimulus material had been presented, Harris's (1974b) subjects were told the following:
recall is a less appropriate task for determing whether any or all possible pragmatic inferences have been made. For example, Monaco (Note 5) used a narrative passage containing five paragraphs and a descriptive passage containing four paragraphs. One paragraph from the descriptive passage was the following:
It was a log cabin. The cabin had no porch. The chairs were old. The chairs had pillows.
Because of the complexity of the sentences in the original paragraph, cued recall would be ill-advised in this situation since the subject, could not be expected to reproduce these sentences in their entirety. To ask for complete, verbatim free recall by the subjects, on the other hand, would produce seriously incomplete protocols that would be difficult to score and would not be an accurate reflection of the pragmatic inferences made, since so much material would not be produced. Johnson et al. (1973) used a verbatim recognition memory task in their study of implications. Here, subjects who had been presented with two-sentence paragraphs were to identify whether test sentences were "actually presented" to them during the study phase (i.e., were the test sentences quoted word for word from the study material) by identifying the test sentences as either "old" (exact quotations from the study material) or "new." Problems with this type of test are two-fold. First, since more than one pragmatic implication may be conveyed in any given sentence, the subject could falsely identify one of the pragmatic implications in an altered sentence as old (making the pragmatic inference) and correctly identify the other as new (not making the pragmatic inference). In this case, he would identify the entire sentence (and both pragmatic implications, as far as the scoring is con-
Below are several sentences about the content in the sentences you just heard. You are to check the blank to indicate whether the written sentence is true, on the basis of the oral sentence; false, on the basis of the oral sentence; or indeterminate (oral sentence did not make clear whether written sentence is true or false). The written sentences will not be the same wording as the oral ones, but the content is the same; it is your memory for ideas, not exact words, that is of interest here. (p. 29)
PSYCHOLOGY OF PRAGMATIC IMPLICATION
11
In the case of Paragraph 57a, for example, hypothesis—but not to fully explore the Sentences 57b through S7e are all logically probabilistic nature of inferring Sentence indeterminate as to their truth value. How- 59b from Paragraph 59a. If in fact they had ever, subjects making the pragmatic infer- included the "indeterminate" alternative ences in Sentences 57b-57e circle "true" along with true and false, it is possible that after those statements; thus, indicating their subjects would have chosen to identify that they had in fact made the pragmatic sentences like 59b as "indeterminate" inferences, that is, they understood that rather than as "false"; and with these rethose statements were true. By using this sults, they may have been able to more recognition-of-information test, the experi- accurately interpret their data. A similar menter can directly test the subject's under- experiment by Singer (1976) found constanding of each piece of information ex- flicting results that might have been more pressed in or implied by the study material, interpretable and reconcilable with Keenan rather than the subject's memory for the and Kintsch had the third response category surface structure of the study material. been used. An additional advantage to the recognition-of-information test is that the experi- Construction and the Locus of Pragmatic menter can study with equal ease the Implication subject's performance on logical inference and asserted statements that may also be Bartlett (1932) described memory in related to the original study material. Per- terms of a constructive process that inteformance may be compared with that on grates stored information when the subject pragmatic implication items. Clearly false is asked to remember (retrieve from memand clearly indeterminate filler test sen- ory). When recalling to-be-remembered tences may be used to control response passages, Bartlett's subjects often included biases and act as comparisons to inferred information not presented in the original material. passage while deleting other information Finally, it is necessary to stress the im- that was presented in the passage. For this portance of including the indeterminate reason, Bartlett hypothesized a construcalternative in the recognition-of-informa- tive memory that, on retrieval, integrates tion test for the study of implications/ the stored information so that it conforms inferences. Keenan and Kintsch (1974) with the individual's world view. This inteused paragraphs like gration is gained at the expense of accuracy 59a. A burning cigarette was carelessly discarded. of comprehension of the once-new informaThe fire destroyed many acres of virgin forest. tion through "simplification," described by and asked subjects to identify the statement Bartlett (1932) as S9b. A discarded cigarette started a fire.
as either true or false. As Monaco (Note S) pointed out, Sentence 59b is pragmatically implied by Paragraph S9a and is therefore logically indeterminate with respect to Paragraph S9a. Keenan and Kintsch (1974) note that Sentence 59b must be inferred in order for Paragraph 59a to be meaningful, that is, that Sentence S9b was necessarily true with respect to Paragraph 59a. However, enough of their subjects responded "false" to test sentences like 59b, when presented with paragraphs like 59a, for Keenan and Kintsch to reconsider their experimental
due to the omission of material that appears irrelevant, to the construction gradually of a more coherent whole, and to the changing of the unfamiliar into some more familiar counterpart, (p. 138)
In the more recent psycholinguistic literature, there has been a reemphasis on the constructive nature of memory. This reemphasis was made explicit by Brockway, Chmielewski, and Cofer (1974) who stated that a theory of memory must postulate mechanisms or processes which (a) represent the temporal and other features of experienced episodes, (b) are capable of producing accurate recall and recognition, (c) on occasion produce highly inaccurate reconstructions of what was presented in the past, (d) identify
12
RICHARD J. HARRIS AND GREGORY E. MONACO
the conditions which control the occurrence of accurate versus inaccurate performance, and (e) provide for operations which, working on the contents of memory, can generate information not previously stored as such. (p. 195)
sentences. Subjects heard
The last three conditions were included by Brockway ct al. to account for results obtained by Bartlett and other experimenters that supported construction. Beginning with Bartlctt's (1932) work, it is clear that the study of implication and inference is a study of the construction process. Bartlett's subjects simplified by inferring material that was only pragmatically implied in the original passage. For example, "That Indian has been hit" was recalled as both "An Indian was wounded by an arrow" or "An Indian was shot." This suggests that the original phrase implied an instrument. Other subjects rather frequently inferred that the story concerned several Indians, even though only one character was said to be an Indian. Bartlett himself stated that "It is a matter of very considerable interest that even the most elementary looking perceptual processes can be shown frequently to have the character of inferential construction" (p. 33). More recent investigators such as Bransford, Barclay, and Franks (1972) have found supporting evidence for Bartlett's construction hypothesis by having subjects study sentences and passages containing logically implied relations, such as
and falsely recognized
60a. Three turtles rested on a floating log and a fish swam beneath it.
and then testing subjects on recognition memory for new sentences that were logically implied by those studied, such as 60b. Three turtles rested on a floating log and a fish swam beneath them.
Subjects consistently identified new, logically implied sentences like 60b as old. In a second experiment reported in the same article, subjects consistently recalled sentences like 60a as 60b, suggesting that logical inferences were constructed. Johnson, Bransford, and Solomon (1973) found that subjects in their experiment recognized as old sentences that were pragmatically implied by the original study
61a. John was trying to fix the birdhousc. Me was pounding the nail when his father came out to watch him and to help him do the work.
61b. John was using the hammer to fix the birdhouse when his father came out to watch him and to help him do the work.
as old. It is clear that the use of a hammer is only pragmatically implied by Paragraph 61a. Bartlett, in his work on construction and constructed inferences, placed the locus of the construction process at retrieval. Other research has indicated, however, that this may not be the case. Bransford and Johnson (1972) found that thematic information in the form of a picture or title that was presented to the subject prior to presentation of a passage served to aid the subject's organization of passage information, as measured in subsequent recall, more effectively than nonpresentation of the thematic information or presentation following the passage. Likewise, Dooling and Mullet (1973) found that a thematic title presented prior to a passage aided both recall and recognition of the passage more effectively than presentation of the thematic title after the passage. If the construction occurred at retrieval, one would expect a theme presented just before recall to be a more effective memory aid than it was found to be. However, the BransfordJohnson and Dooling-Mullet effects of better recall and recognition when thematic information is presented prior to the passage are confounded with paragraph comprchensibility. The passages may not be attended to as well when thematic information is absent during paragraph presentation, that is, when presented at retrieval ; however, even if attended to, the passages make little or no sense without thematic information, thus leading to poorer comprehension. Monaco (Note 5) hypothesized that construction takes place during storage and proceeded to test his construction-in-storage hypothesis with pragmatic and logical implication. Passages containing these im-
PSYCHOLOGY OF PRAGMATIC IMPLICATION plications are comprehensible without the presentation of any additional information, thus offering a better control for comprehensibility and attention than the thematic studies. (It should also be noted that passages containing these implications offer two dependent measures: number of pragmatic inferences constructed and number of logical inferences constructed.) Monaco (Note 5) used passages that pragmatically implied certain information in a number of ways. The entire passage could pragmatically imply a particular idea, while words, individual sentences, or groups of sentences could pragmatically imply other information. For example, 62. Jose arose early in the morning. After dressing, he ate breakfast and then went over to the neighborhood school. He was pleased that the sun was shining today.
was the first paragraph of a narrative passage discussing an episode in the life of the character Jose. Monaco found that one group of subjects given a subsequent recognition-of-information test identified as "true" statements such as 63a. Jose was a student. 63b. Jose walked to school.
Paragraph 62 pragmatically implied Sentences 63a and 63b to the subjects, although their truth value is logically indeterminate with respect to the information in Paragraph 62. It is difficult to identify which sentence or word in Paragraph 62 carried the implications, and it is more than likely that Sentences 63a and 63b are suggested by the entire paragraph. It is also entirely possible that, since Jose's status at the school is never mentioned in the entire passage, the subject "fills in" what is left unstated, as Clark (Note 6; Haviland & Clark, 1974) suggests. Such inferences are probabilistic and, thus, may possibly prove later to be incorrect. In Experiment 1, Monaco (Note 5) found that subjects made significantly fewer pragmatic inferences like Sentences 63a and 63b when they were instructed, before passage presentation, that they would receive a multiple-choice test after hearing the passages, than did subjects
13
who were instructed, before presentation, that they would receive an essay test after hearing the passages, F'mm(l, 47) = 5.10, p < .05. Both groups, however, made the same number of logical inferences. This evidence further supported the construction-in-storage hypothesis for pragmatic inferences. Monaco (Note 5) went on to test the hypothesis more directly. In Experiment 2, the same two paragraphs were again used, but instructions (multiple choice or essay) were given between passage presentations. The construction-in-storage hypothesis predicts no difference between groups on implication items in the recognition-ofinformation test for the first passage (because both groups were under a noinstruction condition when this passage was presented), but it does predict a difference in favor of the multiple-choice group on implication items in the second passage test. On the other hand, the construction-in-retrieval hypothesis predicts a difference between groups on tests for both passages because instruction information was present for both passages during retrieval. The predicted results for Experiment 2 (an interaction of instructions by test) were obtained for logical implications, ^'min = 10.96, p < .005. These results clearly supported the construction of logical inferences in storage. A third experiment by Monaco (Note 5) used a manipulation similar to that of Dooling and Mullet (1973) and Bransford and Johnson (1972) for the purposes of demonstrating that construction of both pragmatic and logical inferences occurred in storage, that the Dooling-Mullet and Bransford-Johnson effects mentioned above were in fact artifacts of incomprehensible stimulus materials, and that the storage or construction of a representation of stimulus material presented in the form of a prose passage is not complete until unrelated information (in this case, the presentation of a second unrelated prose passage) begins to be processed. Rather than manipulating thematic information, Monaco manipulated the presentation of a key sentence describing the occupation of the main char-
14
RICHARD J. HARRIS AND GREGORY E. MONACO
actcr, with the key sentence occurring at the end of the related passage (storage) or at the end of the unrelated passage (retrieval). The results of Monaco's Experiment 3 confirmed all three hypotheses. Construction of both pragmatic and logical inferences was found to occur in storage; the Bransford-Johnson and Dooling-Mullet "retrieval" group was found to be, as predicted, a storage group indicating that construction of a representation of interrelated material is not complete until unrelated information begins to be processed. Monaco's (Note 5) series of experiments have not only produced significant evidence that inferences are constructed in storage, they also "provide data indicating that, since construction of logical and pragmatic inferences may be differentially affected by various experimental manipulations, the logical-pragmatic distinction is psychologically distinct as well" (p. 36). Although they typically have not made the logical-pragmatic distinction overt or used an indeterminate response category, some reaction time studies comparing time to verify implicitly versus explicitly presented material may also be interpreted as support for construction of inferences in storage. For example, Keenan and Kintsch (1974) and McKoon and Keenan (1974) found that, while subjects questioned from 0-30 seconds after reading a paragraph took longer to answer questions about implicitly than explicitly presented material, those questioned 15-20 minutes or 48 hours later showed no implicit-explicit difference. They used these results to argue that, after the short period of time when the surface structure of the paragraph is still at least partially available in one's short-term memory, questions are answered from a conceptual, not a linguistic, base. The failure to find a reaction time difference at the longer time intervals suggests that the inferences were made on storage, and the stored semantic information is indistinguishable as to whether it originally had been directly asserted or only inferred. Baggett (1975) obtained similar results using pictorial materials, except for the
difference that surface memory for pictures lasted far longer than surface memory for language. It is likely that the construction hypothesis needs further development in order to adequately account for the ongoing process of language comprehension, for even in the typical experimental task it is apparent that storage takes place both during initial presentation of materials, and storage takes place during retrieval. This is most clearly illustrated in two experiments reported by Loftus and Palmer (1974), where subjects viewed a film of an automobile accident and then responded to a questionnaire. One critical question varied in the first experiment between groups of subjects was 64. About how fast were the cars going when they (hit, smashed, collided, bumped, or contacted) each other?
Speed estimates in response to Question 64 varied significantly with the verb condition, indicating that the verbs differed in their conveyed pragmatic implications about the speed of the cars. In Experiment 2, Question 64 contained either hit or smashed or was entirely absent from the questionnaire. Not only were the original results replicated for subjects given Question 64, but also when questioned 1 week later, a significantly greater number of subjects affirmed the presence of broken glass in the presented film (when no broken glass was present), if they had been presented Question 64 containing smashed. Whereas the difference in speed estimates is directly attributable to the pragmatic implication carried by the verb in Question 64, it is not clear whether the affirmation of broken glass is attributable to the pragmatic implication in the verb in the question or rather to the pragmatic implication in the subject's initial response to that question. This dramatically indicates that the construction-in-storage process is set to work whenever new information is encoded. New information is being encoded whenever a subject attends to new stimuli, whether it is produced by the subject or the experimenter and whether it is presented during the acquisition task or during the retrieval phase of the experimental session.
PSYCHOLOGY OF PRAGMATIC IMPLICATION
Monaco has attempted to expand and refine the construction hypothesis in further experiments dealing with both inference (Note 7, Note 8) and noninference (Note 9) materials. His work with inference materials has demonstrated that certain pragmatic inferences are more consistently constructed by subjects than others. For example, of 72 subjects in Experiments 1 and 2 (Monaco, Note 5), 89% responded "true" to Sentence 63a, thus indicating that they had pragmatically inferred that Jose was a student. Only 5.5% responded with the logically correct alternative "indeterminate." On the other hand, only 61% of the subjects responded "true" to Sentence 63b, indicating that they had pragmatically inferred that Jose walked to school, while 36% responded with the logically correct alternative "indeterminate." Using the same passage and recognitionof-information test, Monaco (Note 8) has demonstrated that certain inferences are made by subjects, even when the speaker's message directly asserts something else. Seventeen out of 22 subjects who were explicitly told at the beginning of the passage that Jose was a teacher responded "true" to Sentence 63a, thus calling Jose a student and demonstrating that the influence of implied material may be even stronger than directly asserted material. Monaco (Note 10) has summarized these and other results and presented a model of the construction process from the input of a speaker's message to final storage of the constructed representation of that message in memory. The model depicts the construction of inferences based on directly asserted information by the speaker as well as inferences previously made by the hearer and information already in memory. Some Practical Applications of Pragmatic Implication Although most of the psycholinguistic study of pragmatic implication has been basic laboratory research, the understanding of this phenomenon has serious and direct application to some important social issues. Three will be considered at this
15
time: (a) the legal issue of the evaluation of eyewitness testimony and courtroom evidence, (b) the effect of commercial advertising on the consumer, and (c) the effect of a doctor's questions in medical diagnosis. Only the legal issue has been extensively researched so far. Pragmatic implications become very important in the psychology of evidence in the courtroom. As suggested by Black (1962), a person on the witness stand is liable for perjury for asserting or logically implying a falsehood but not for pragmatically implying something false. The witness must swear to tell the truth but not necessarily to imply the truth. Consider the following three answers to a prosecutor's questions: 65. Did you steal the money? 66a. I didn't steal the money. (Assertion) 66b. I wasn't able to steal the money. (Logically implies Sentence 66a) 66c. I wasn't forced into stealing the money. (Pragmatically implies Sentence 66a)
In Sentences 66a and 66b, the witness is either directly asserting or logically implying that he did not steal the money. However, in Sentence 66c, he is only pragmatically implying innocence; in this case, the witness would not be liable for perjury if it was found that he did in fact steal the money, for example, Sentence 67. 67. I wasn't forced into stealing the money, but I did steal it (of my own free will).
While building legal safeguards against a subsequent perjury charge, the crafty witness apparently hopes that the court and jurors will, like the subjects of several experiments discussed above, be unable to distinguish pragmatic implications from assertions and logical implications in memory. Such a rinding was obtained by Harris et al. (1975), who found that subjects hearing statements like 66a and 66c were equally likely to answer in subsequent questioning that the witness did not steal the money. "Memories" that the witness did not steal the money were reduced only slightly and nonsignificantly by specific prior instructions about the pitfall of interpreting pragmatic implications as asserted facts. Similar results were obtained
RICHARD J. HARRIS AND GREGORY E. MONACO in questioning immediately or 2 days after the testimony. Such distortion of information in memory is also reflected in memory for nonverbal information, such as that reported by an eyewitness to a crime; such reports may often be unwittingly based on pragmatic inference by the eyewitness. For example, Buckhout (1974) reports cases of witnesses to a crime "remembering" more than they could possibly have seen, apparently filling in unclear details to construct a coherent total impression. Sometimes a physical similarity, such as a like-colored jacket or a person of similar build, will pragmatically imply a suspect's guilt in an eyewitness's mind as the witness tries to remember details of the crime. For a thorough review of eyewitness identification research, see Levine and Tapp (1973). Another courtroom application of pragmatic implication occurs in the leading question (Harris, 1973; Loftus, 1975; Loftus, Altman, & Geballe, 1975; Loftus & Palmer, 1974; Loftus & Zanni, 1975). Although there is no generally used definition, leading questions may be defined as questions . . . which suggest to the witness the answer desired, or which embody a material fact, and may be answered by a mere negative or affirmative, or which involve an answer bearing immediately upon the merits of the cause, and indicating to the witness a representation which will best accord with the interests of the party propounding them. (Black, 1951, p. 1034) As such, the use of leading questions is greatly restricted in the rules of evidence, for example, to instances where the witness has been ruled hostile. It is possible, however, for extremely subtle changes in the wording of a question to have considerable effect on the answer. For example, the definite article the typically precedes a noun whose referent is previously presumed to exist by both speaker and hearer, while use of the indefinite article a makes no such presumption (e.g., Osgoocl, 1971). Loftus and Zanni (1975) showed subjects a film of an automobile accident; in subsequent questioning about the film, questions using the produced fewer "don't know" responses and more false recognition of events that had
not occurred in the film than did questions using the indefinite article a. 68a. Did you see the broken headlight? 68b. Did you see a broken headlight?
Similarly, Loftus and Palmer (1974) found that subjects seeing a similar accident film estimated the speed of the colliding cars to be faster if asked Question 69 than the same sentence with collided, bumped, contacted, or hit in place of smashed. 69. About how fast were the cars going when they smashed into each other? Harris (1973) found that changing the adjective used to question an object's place on some measurable dimension can alter the answer to the question. For example, with no contextual information whatsoever, subjects' numerical responses to Question 70 had a greater variance than responses to Question 71, whose answers were mostly all at the shallow end of the continuum, while responses to Question 70 would be classified as both shallow and deep. 70. How deep was the canal? 71. How shallow was the canal? In a courtroom situation, leading questions may also have an effect on the jury, altering their memory at some future time. For example, Loftus and Palmer (1974) asked subjects Question 69 or the corresponding question with hit after seeing a filmed accident. One week later, subjects who had been questioned with smashed were more likely to answer "yes" to Question 72 than subjects previously questioned with hit, when no subject had really seen broken glass. 72. Did you see any broken glass? Loftus et al. (1975) showed subjects a film of a classroom protest demonstration and then asked questions that used either aggressively worded or passively worded questions. One week later, subjects who had been questioned with aggressively worded questions rated the filmed incident as beingnoisier and more violent, the demonstrators as more belligerent, and the students in the classroom as more antagonistic than
PSYCHOLOGY OF PRAGMATIC IMPLICATION subjects questioned with passively worded questions. This effect of such labeling on memory has also been found in reproductive and recognition memory for ambiguous visual forms (Carmichael, Hogan, & Walter, 1932; Daniel, 1972). Another evidentiary application of pragmatic implication is found in improper sorts of evidence that the jury is asked to disregard in its deliberations. For example, if a prosecutor examines the defendant with Question 73, the defense attorney will most likely object and be sustained by the judge, who will then ask the jury to disregard the improper question. 73. Were you at all influenced in what you did on the night of March 5 by the fact that you (a) used to belong to the Ku Klux Klan or (b) axed IS people to death in Boston in 1955?
Each juror may conscientiously try to do so, but the pragmatic implications of the question may remain. If, for example, a black juror tries not to consider the fact that the defendant may have once belonged to the Ku Klux Klan, the juror may still have stored in memory something about the defendant hating blacks, a pragmatic implication of the improper question. Since the juror may likely not realize where that bit of information came from, he would not know it should be disregarded. In a jury simulation study, Sue, Smith, and Caldwell (1973) have shown that jurors do indeed use evidence ruled inadmissible in reaching a verdict. More generally, much of the evidence presented at a trial is offered, not for the facts it introduces, but rather for the information it pragmatically implies. Character witnesses are a clear example of this. Testimony from past associates that the defendant is a fine, upstanding member of the community, a model husband and father, and so on says nothing definitive about his whereabouts on the evening of the murder, but strongly pragmatically implies something about the likelihood of his guilt. Such implications are not lost on the jury. The same is true for unfavorable evidence introduced in the form of statements about past crimes, mental aberrations, or sexual deviance of the defendant.
17
A tacit recognition of the importance of such pragmatic implications is reflected in the current feminist campaign for laws to prohibit a defense attorney in a rape trial from introducing evidence about the victim's sexual experience prior to the crime. Another type of evidence based on pragmatic implication is the case where a defendant's guilt is implied through calculations of mathematical probabilities designed to underline the small probability of finding someone else who meets all the characteristics reported by eyewitnesses (Finkelstein & Fairley, 1970; Weeks, 1975). For example, if some mathematician computes that the probability of finding a couple other than the defendants who meet all the characteristics (e.g., both 20-25 years old, interracial couple, yellow Dodge hardtop with bent fender) observed by bystanders watching them leave the scene of the crime is one in twelve million, the jury may pragmatically infer the couple's guilt; although, the evidence directly said nothing at all about their guilt or innocence as such. A further example of the use of pragmatic implications in evaluation of evidence may be found in an examination of certain passages from the Nixon White House tapes revealed in the Watergate affair (The Presidential Transcripts, 1974). These conversations were presented in evidence in the Watergate conspiracy trials of 1973-1974. In them are many places where what is pragmatically implied may be as critical as what is directly asserted. For example, Nixon says, "Nobody ever told me a damn bit of this, that Mitchell was guilty" (p. 249), pragmatically implying that he did not know Mitchell was guilty, but not inconsistent with his knowing that fact by some other means than oral communication. Similarly, when Nixon says, "And I just feel that I have to be in a position to be clean and to be forthcoming" (p. 354), he is only pragmatically implying that he is in fact clean and forthcoming. Either of the above examples, and dozens of others as well, could have been critical in a courtroom in determining if the person in question later contradicted himself in a public statement; contradiction of a pragmatic
18
RICHARD J. HARRIS AND GREGORY E. MONACO
implication would not be grounds for legal action. Another applied area where the comprehension and/or memory of pragmatically implied material as definitively asserted becomes critical is advertising. Although the whole question of what constitutes deception in advertising is controversial (see Garfinkcl, in press, Note 11), one cannot make false assertions about a product without being liable for misrepresentation. Making false implications about the product, however, leaves one considerably less vulnerable. If, as studies cited above have shown, people remember implied material as asserted, fraudulent advertisers may be able to have their intended effect without subjecting themselves to prosecution. In a potential landmark case currently in appeal, lower courts have ruled against Warner-Lambert, makers of Listerine Antiseptic (a mouthwash), for advertising by pragmatically implying false claims, which had created a "lingering false belief." Although the court ruled that this false belief "must be dispelled," the case is still in appeal and may well be decided by the U. S. Supreme Court. 3 Two studies in progress (Harris, in press; Bruno, Note 4) used the same recognitionof-information task used by Harris (1974), Harris et al. (1975), and Monaco (Note 5) to study the memory and comprehension of pragmatic implications presented in radio commercials. The subjects heard taperecorded mock commercials that cither directly asserted or pragmatically implied claims about some fictional products. For many of the commercials, including some based on actual television advertising, subjects did not distinguish between asserted and pragmatically implied claims, thus replicating the results found in the laboratory and the mock courtroom situation. Specific instructions about pragmatic implications moderately improved discrimination of assertions and implications (Harris, in press). A third applied area in which pragmatic implication is potentially critical is in medical and psychotherapcutic diagnosis. Much as a questioning attorney can direct
a witness's thoughts with a leading question, so can a doctor direct a patient's thoughts when the latter is being questioned about his ailment. Although no complete study has been done on this problem, its potential importance is suggested by an informal experiment reported by Loftus (1975). She asked subjects cither Question 74a or 74b. 74a. how 74b. how
Do you get headaches frequently, and, if so, often? Do you get headaches occasionally, and, if so, often?
Subjects questioned with 74a reported a mean 2.2 headaches per week, while those questioned with 74b reported only .7. Although a complete, controlled study of this problem is clearly in order, it seems likely that a doctor may pragmatically imply, through the wording of his question, information that may affect how the patient retrieves his symptom occurrences and perceives his own physical condition. The implications in the doctor's questions join with the feedback from the sensory systems of the patient's body to be processed by his mind in interpreting his particular symptoms. It is likely that the most accurate and useful reporting of the patient's symptoms in medical diagnosis is greatly affected by the form of the doctor's questions, as the witness's memory is by a lawyer's questions. 3 The particular Listerine commercial in question was (in part): "Wouldn't it be great," asks the mother, "if you could make him coldproof? Well, you can't. Nothing can do that (boy sneezes). But there is something that you can do that may help. Have him gargle with Listerine Antiseptic. Listerine can't promise to keep him cold-free, but it may help him fight off colds. During the cold-catching season, have him gargle twice a day with full-strength Listerine. Watch his diet, sec he gets plenty of sleep, and there's a good chance he'll have fewer colds, milder colds this year" (Kilpatrick, 1975). A verbatim text of this commercial, changing only the product name to "Gargoil," was used by Harris (1977) as an experimental item. In his Experiment 1, all of the IS subjects hearing the above later checked the statement "Gargling with Gargoil Antiseptic helps prevent colds" as true, this in spite of some disclaimers and hedges in the advertisement itself (you can't, can't promise, may help, a good chance).
PSYCHOLOGY OF PRAGMATIC IMPLICATION
Even doctors themselves may be prone to diagnose incorrectly due to the interpretation of inferred material as fact. A provocative study by Johnson-Abercrombie (1960, also reported in Slovic, Fischhoff, & Lichtenstein, Note 12) found that medical students studying x-rays of hands appeared not to recognize the difference between factual information (e.g., size, shape, number of bones) and probabilistic inferences (e.g., age and absolute size of hand), and that they interpreted both as facts. Johnson-Abercrombie (1960) concluded that The inferences the students had made were not arrived at as a series of logical steps but swiftly and almost unconsciously. The validity of the inferences was usually not inquired into, indeed, the process was usually accompanied by a feeling of certainty of being right, (p. 8a)
Concluding Remarks
It seems worthwhile, in conclusion, to briefly consider some additional extensions of the psychology of pragmatic implication beyond psycholinguistics. For example, pragmatic implication may in principle be the same as what is involved in certain nonverbal decision-making and social situations. For example, the whole area of Bayesian decision making (e.g., Edwards, Lindman, & Phillips, 1965) may be interpretable as pragmatic implication: A prior probability would suggest (pragmatically imply) a likely interpretation, choice, and so on. With the presentation of new information, the subjective probability may be revised such that the posterior probability may suggest the same outcome (confirmation of pragmatic implication) or a different one (denial of pragmatic implication). Some researchers in the area of decision making in general have shown some signs of interpreting some of their findings in terms of pragmatic inferences constructed by the subjects and the interaction of these inferences with stored knowledge. For example, in an interpretation of his studies of the hindsight bias in the estimation probabilities (Fischhoff, 1975; Fischhoff & Beyth, 1975), Fischhoff (1977) has concluded Upon hearing the answer to a question . . . people may immediately integrate that answer with what-
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ever else they know about the topic. The purpose of this integration is to create a coherent whole out of all relevant knowledge. , . . These processes are so natural and immediate that people don't appreciate the effect that hearing the answer has had on their perceptions. . . . Even when told to do so, it is evidently extremely difficult to deprocess so important a bit of information, (p. 356)
Even statistical inference in general may involve pragmatic implication. For example, an alpha level of .01 pragmatically implies that the null hypothesis in question may be rejected. But as often as 1% of the time, such an inference would be incorrect and the obtained difference would not in fact be real in the population from which the sample was taken. Unlike mathematical inference of the sort involved in theorem proving, which is logical inference, statistical inference is always pragmatic. The practical applications of pragmatic implication, which have been at least implicitly understood by attorneys and advertising agencies for many years, are only recently being explored by the psychologist. Further applications within the field of psychology as well as education may be possible as well. Monaco's (Note 5) results suggest that students have the ability to make or refrain from making pragmatic inferences to maximize their chances of doing well on a test. Further research may determine how one acquires this ability, in what situations (including the classroom) it is useful, and how to further develop this ability (e.g., Bruno, Note 4). There may even be important applications of pragmatic implication in morality and theology. For example, Bender (Note 13) in a discussion on telling the truth suggests that the moral inappropriateness of lying may well extend beyond the statement of false assertions to include various types of implicational lying, such as the deceptive omission of critical information (cf. Garfinkel, Note 11, for advertising applications) and social stereotyping, that is, the holding of pragmatically inferred overgeneralizations about certain social groups. Further research in progress will probably be able to extend the usefulness of pragmatic implication to a deeper understanding of attitude change. For example,
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RICHARD J. HARRIS AND GREGORY E. MONACO
Harris (Note 14) has varied initial information (favorable or unfavorable) presented to subjects about an American president. The resulting impression formed may affect the probability of a positive and/or negative pragmatic inference being drawn, as assessed later on a recognition-of-information test. In an investigation of the effects of subjects' attitudes on the drawing of pragmatic inferences, Monaco (Note 15) is currently testing subjects' comprehension of a debate. By pretesting, the subjects were dichotomized into either (a) pro- or anti-abortion or (b) pro-Carter or pro-Ford (for a debate on the 1976 presidential election). The independent variables were subject's sex, subject's attitude toward the issue, the sex of the debater presenting the opinion with which the subject agreed, and the type of debate. The dependent variables were logical and pragmatic inferences constructed by subjects, as revealed on a subsequent recognition-of-information test. If subjects do process information differently based on the type of information, the source of the information (in this case, sex of the debater), and their own opinions, significant interactions would be expected. A valid intuition, for example, would be that a woman would find another woman speaking in favor of abortion more credible (and therefore construct more pragmatic inferences) than a man; yet, the woman might find a man more credible on the subject of politics. Answers to questions such as these have the potential of expanding greatly our knowledge of the communication process and adding critical insights to the findings of the classic attitude-change literature. It is clear that the phenomenon of pragmatic implication must be a part of any global theory of comprehension and/or memory. If, as the evidence at this point suggests, inferential processes occur primarily at storage rather than retrieval, then information stored in memory, in whatever its form, includes both logical and pragmatic inferences made from the stimulus material. This inferred information is constantly being rearranged, modified, and
restructured with subsequent stimulus input into the information-processing system. Although the focus of most global theories of memory (e.g., Anderson & Bower, 1973; Kintsch, 1974; Rumelhart, Lindsay, & Norman, 1972) is on the nature of the stored material in memory, the probabilistic processes used to develop the initial semantic interpretations that are stored must also be considered. That which is only pragmatically implied is at times functionally equivalent to that which is directly asserted. Reference Notes 1. Brewer, W. F. Memory for the pragmatic implications of sentences. Unpublished manuscript, 1974. (Available from W. F. Brewer, Department of Psychology, University of Illinois, Champaign, Illinois 61820.) 2. Osgood, C. E. Personal communication, February 1974. 3. Harris, R. J. The effects of instructions, group size, and witness characteristics on memory for pragmatic implications from courtroom testimony (Report No. 76-12A). Manhattan, Kansas: Kansas State University, Human Information Processing Institute, January 1977. 4. Bruno, K. J. The, distinction of pragmatic implications and direct assertions by adolescents. Unpublished master's thesis, Kansas State University, 1977. 5. Monaco, G. E. Construction as a storage phenomenon. Unpublished master's thesis, Kansas State University, 1976. (Available in abridged form from G. E. Monaco, Department of Psychology, Kansas State University, Manhattan, Kansas 66S06.) 6. Clark, H. H. Comprehension and the Given-New contract. Paper presented at the conference on the Role of Grammar in Interdisciplinary Linguistic Research, University of Bielefeld, Bielefeld, Germany, December 1973. (Avaliable from H. H. Clark, Department of Psychology, Stanford University, Stanford, California 94305.) 7. Monaco, G. E. Mediation processes in the comprehension of English spoken with a foreign accent. Research in progress, Kansas State University, 1976. 8. Monaco, G. E. Is that a fact? Manuscript in preparation, Kansas State University, 1976. 9. Monaco, G. E. The role of storage in the construction of non-inference material. Unpublished manuscript, Kansas State University, 1976. 10. Monaco, G. E. Construction reformulated. Unpublished manuscript, Kansas State University, 1976.
PSYCHOLOGY OF PRAGMATIC IMPLICATION 11. Garfinkel, A. Linguistic aspects of truth in advertising. Paper presented at the Fourth Annual Conference on New Ways of Analyzing Variation, Georgetown University, Washington, D.C., October 1975. (Available from A. Garfinkel, Department of Linguistics, Georgetown University, Washington, D.C.) 12. Slovic, P., Fischhoff, B., & Lichtenstein, S. The certainty illusion. ORI Research Bulletin, February 1975, 16(4). (Available from Decision Research, 1201 Oak Street, Eugene, Oregon 97403.) 13. Bender, K. B. To tell the truth. Unpublished manuscript, August 1976. 14. Harris, R. J. The effect of initial impression formation on pragmatic inferences drawn. Research in progress, Kansas State University, 1977. 15. Monaco, G. E.. The effect of attitudes on comprehension. Research in progress, Kansas State University, 1977.
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Received May 19, 1976 •
