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A new pedagogy for explanatorypublic speaking: Why arrangementshould not substitute for inventionKatherine E. Rowan aa Associate Professor in the Department of Communication ,Purdue University , West Lafayette, IN, 47907Published online: 18 May 2009.

To cite this article: Katherine E. Rowan (1995) A new pedagogy for explanatory publicspeaking: Why arrangement should not substitute for invention, Communication Education,44:3, 236-250, DOI: 10.1080/03634529509379014

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A NEW PEDAGOGY FOR EXPLANATORYPUBLIC SPEAKING: WHY

ARRANGEMENT SHOULD NOTSUBSTITUTE FOR INVENTION

Katherine E. RowanBecause of its eighteenth- and nineteenth-century roots, current informative speaking

pedagogy emphasizes arrangement rather than invention. Today's pedagogy providesspeakers with a rich array of possibilities for organizing speeches but gives little systematicassistance in anticipating and overcoming audiences' likely sources of confusion. Becauserhetorical forms themselves do not make complex ideas clear, this approach is inadequate.Speakers attempting to inform need heuristics or diagnostic frameworks for determiningwhy complex material is apt to confuse. They also need tested methods for avoiding suchconfusions. This essay offers a new pedagogy for explanatory speaking, a type ofinformative speech, built around such heuristics. This pedagogy is supported by classicalrhetoric's emphasis on the importance of invention or inquiry prior to presentation and bydecades of contemporary educational research. In essence, this new pedagogy castsinformative speaking as an explicitly strategic enterprise for which there is importanttraditional and recent empirical guidance.

In many ways, contemporary textbook treatments of informative speaking areimpressive. Verderber's (1994) ninth edition of The Challenge of Effective Speak-ing, for example, uses testimonials from professional speakers, eye-catchinggraphics, a rich array of examples, and expert advice to assist student speakersin producing well-prepared and well-delivered informative presentations. In-deed, the informative speaking sections in top-selling textbooks like Beebe andBeebe (1994), DeVito (1990), Lucas (1992), Nelson and Pearson (1990), Osbornand Osborn (1994), and Verderber (1994) seem so sound that one might thinkthere was relatively little one could do to improve them.1

There is, however, an important way in which instruction in informativespeaking can be refined. Textbooks could give informative speakers more helpwith strategy, particularly for the speech that explains a difficult idea.2 Speechesof this sort help audiences understand topics such as how we see colors, what"Manifest Destiny" means, or why abstract art can be more technically challeng-ing than portraiture. The principal help students need with the "speech toteach" is guidance in increasing the likelihood that the audience truly learnsfrom it.

Unfortunately, this assistance is not readily available. In current treatments ofinformative speaking, advice on arrangement substitutes for inventional guid-ance. Unlike coverage of persuasion where students are guided to considerlikely obstacles to agreement and research-supported methods for overcomingthem, in treatments of informing, students are not aided in considering likely

Katherine E. Rowan (Ph.D., Purdue University) is an Associate Professor in the Department ofCommunication at Purdue University, West Lafayette, IN 47907.

COMMUNICATION EDUCATION, Volume 44, July 1995

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PEDAGOGY FOR EXPLANATORY SPEAKING—237

obstacles to intellectual understanding. Rather, the focus is on ready-made"solutions" or arrangement forms. Typically, these chapters suggest studentsuse definitions, examples, visual aids, and some type of organizational frame-work. Often it is suggested that a "variety" of these techniques be used in hopesthat one or more will work, the level of insight here being somewhat similar tothe status of medicine before the discovery of infectious diseases. Prior to the latenineteenth century, physicians knew certain drinking wells were associated withcholera but could not say why. They did not know the human fecal matterfouling the water contained cholera-causing microbial organisms. Similarly, thebest treatments of informative speaking currently say certain message featuressuch as short sentences, examples, analogies, and the like are useful in explain-ing difficult ideas. But they do not specify when and why certain techniques"cure" frequent forms of confusion (and when these techniques cause moreconfusion).

If we did not know the most frequent sources of difficulty in masteringcomplex information, we would be forced to keep our teaching of informativespeaking at its current stage. However, decades of contemporary educationalresearch have identified key causes of confusion and tested techniques forovercoming them. Further, the classical rhetorical tradition has always stressedthe importance of systematic obstacle analysis prior to making decisions aboutinformation arrangement. Consequently, this essay draws from classical rhetori-cal theory and contemporary research to present a new, invention-emphasizingpedagogy for an important type of informative speaking.

To show why treatments of informative speaking even in our best textbooksare frequently less useful to students than treatments of persuasion, I first offer abrief history of the teaching of expository discourse. Second, I define explana-tory speaking, identifying its relation to informative speech. Third, a pedagogyfor explanatory speaking is presented, one built on the classical rhetoricaltradition and contemporary research. Finally, I describe implications of this newpedagogy for teacher training, student study skills, and assessment of informa-tive speaking skills.

TRADITIONAL CONCEPTUALIZATIONSOF INFORMATIVE DISCOURSE

Speech communication and English composition texts frequently have sectionson expository or informative speaking and writing, expository being the moretraditional term and the one more often used in composition texts. As tradition-ally conceived, expository discourse is principally concerned with the presenta-tion of subject matter. The terms exposition and expository mean setting forth,disclosing, unmasking, or explaining in detail.

EXPOSITION IN EIGHTEENTH-CENTURY RHETORICS

The classical rhetorics of Greece and Rome emphasized persuasive rather thanexpository discourse (Howell, 1973). Expository discourse received greaterattention from eighteenth-century rhetoricians like Hugh Blair, Richard What-ely, and George Campbell. Campbell, particularly, stressed the importance ofexposition in enhancing understanding. Drawing from John Locke and DavidHume, he argued that the world is known by identifying certain ubiquitous

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structures in it. Further, the human mind was held to operate by universal,associative patterns. These realist premises led Campbell to reason that effectiveand efficient communication would occur when subject matter was presented inthe associative patterns that naturally appeal to the minds of audiences (Camp-bell, 1988/1776; Golden &Corbett, 1968;Howell, 1971, 1973). Thus, the task ofa rhetor was to locate the patterns inherent in subject matter and practice theireffective use.

Campbell believed that those seeking to persuade others first had to establishunderstanding in the minds of audiences by using the techniques of exposition.Thus, exposition, in this realist perspective, was an exercise in revealing puresubject matter. Since the subject matter suggested its own arrangement, mini-mal consideration of speakers' and audiences' purposes was needed. Thisapproach to exposition or informative discourse equated informing with arrange-ment.

EXPOSITION IN NINETEENTH AND TWENTIETH CENTURY TEXTBOOKS

The "patterns of exposition" or "modes of discourse" became the organizingframeworks for best-selling composition textbooks in the nineteenth and twenti-eth centuries (Berlin, 1984, 1987; Johnson, 1991). The "Forms of Support" and"Informative Speaking" chapters in today's public speaking books have theirroots in textbooks such as Alexander Bain's English Composition and Rhetoric(1866, cited by Connors, 1981), which was organized to teach expositionalpatterns like narration, description, and definition. In the last two centuries,numerous composition and public speaking textbooks have equated informingwith selection or mastery of forms of support (Berlin, 1984, 1987; Connors,1981; Johnson, 1991; Kinneavy, 1971). The problem with this approach liesneither with the forms of support nor with any particular textbook. It liesinstead with substituting "forms of support" for systematic anticipation of likelyconfusions. Further, the realist assumptions underlying conceptions of exposi-tory or informative discourse are also problematic. Unlike Campbell, we nolonger view informative communication as a process of revealing "pure truth"inherent in subject matter. Contemporary epistemologies view communicationas a process whereby communicators negotiate shared meanings. In a contem-porary constructivist perspective, informing should be viewed as a process ofanticipating and overcoming potential misunderstandings or confusions.

DIFFICULTIES IN EQUATING INFORMING WITH ARRANGEMENT

Several pedagogical problems have arisen from equating informative speakingwith arrangement. First, even in today's best public speaking textbooks thepurpose of informative speaking is not clear. This confusion is not surprising.Because of its realist roots, the term expository or informative discourse hasseveral meanings. It sometimes refers to a type of subject matter (all nonfiction),sometimes to a goal (informing or teaching), and sometimes to arrangementforms themselves. Although today's textbooks could classify informative speechesby goal (e.g., the speech to teach), they usually classify on the basis of form (e.g.,speeches that describe, define, or demonstrate [DeVito, 1990] or speeches aboutobjects, processes, events, and concepts [Lucas, 1992]). Unfortunately, classify-ing by form causes some textbook treatments to imply wrongly that adherence

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to a certain form is what designates a speech as informative. One sample speechin DeVito's (1990) informative speaking chapters is a presentation defining"leadership" and urging the audience to believe that the pursuit of excellence isthe essence of true leadership. Although the speech's goal seems epideictic orpersuasive, it is placed in the chapters on informing presumably because of itsrhetorical form—definition. Another sample speech in DeVito's informativespeaking unit is a commencement address with the thesis, "Use time wisely" (pp.226-229). Again the speech's purpose seems epideictic or persuasive ratherthan informative. Of it, De Vito writes: "This speech is probably best thought ofas one of description, but it is really a combination of information and persua-sion" (p. 228). The latter half of this sentence suggests DeVito's own goodinstincts are more on the mark than his classificatory scheme.

Some sample speeches, though classified by form, are in fact informativebecause of their purpose. They attempt to enhance understanding. For ex-ample, a speech in Monroe and Ehninger (1969) explains why ice floats.Verderber (1994) presents a sample informative speech on the nature andtreatment of dyslexia; Lucas (1992) includes one on the medicinal and culinarybenefits of dandelions. These speeches clearly aim to broaden understandingabout some topic. But the fact that even some textbook authors exhibit confu-sion over what constitutes an informative speech suggests that we err in makingform a classificatory principle. As Kinneavy (1971, pp. 28-29) has argued,rhetorical forms like defining, describing, and demonstrating are means notends. We define, demonstrate, and narrate for many purposes: to inform, persuade,or entertain. Classification by forms such as definition, demonstration, andnarration draws analysis of speech inappropriately toward analysis of form forform's sake rather than toward questions about effectiveness.

A second problem with over-focusing on form is that it blunts consideration ofinformative strategy. Current pedagogy identifies informing with selecting arhetorical form (e.g., defining, narrating) just as eighteenth- and nineteenth-century rhetorics did. Of course, these rhetorical forms can be viewed asfrequent solutions to challenges that informative speakers face. There is aproblem, however, with substituting "form selection" for inventional inquiry. Itreduces the likelihood that informative speakers will systematically diagnosetheir genuine informative challenges. This by-passing of invention (and movingimmediately to arrangement) has apparently been normative in informativespeaking pedagogy for most of this century. Monroe (e.g., Monroe, 1945;Monroe & Ehninger, 1969) is famous for the motivated sequence, the strategicapproach to the teaching of persuasive speaking. But in his treatment ofinformative speaking, he explores strategy only for gaining an audience'sattention and establishing the audience's need for certain information (Monroe,1945). To assist speakers in anticipating an audience's conceptual difficulties, heoffers organizational forms (e.g., time order, space, causal, p. 125).

Monroe's pattern is still followed today. Despite the fact that Beebe and Beebe(1994) emphasize audience analysis throughout their textbook, like nearly all inuse today, they wrongly imply that rhetorical forms themselves make confusingideas understandable. For instance, one speech outlined in the chapter oninformative speaking is designed to inform the audience about liberationtheology (pp. 315-316). At the speech's end, the speaker expects the audience to

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be able to "discuss the definition and origin of liberation theology in LatinAmerica" (p. 315). That is, a clear statement of purpose and a behavioralobjective are presented. What is missing is an analysis of why the audience mayhave trouble meeting the speaker's expectation. What obstacles will they encoun-ter in understanding the definition of this concept and its history? What are thefrequent obstacles people face when attempting to learn a new concept? Whatare the frequent obstacles encountered when people attempt to follow a history?Instead of addressing these issues this textbook, like most, offers minimalinventional guidance. The authors write: "Luisa [the speaker] decided that themost logical way to explain liberation theology was to talk first about thedefinition of liberation theology and second about its origins. She chose a topicalorganization—a logical division of available information about liberation theol-ogy" (p. 316). Note here the assumption that the forms definition and topicalorganization will by themselves explain complex information to an audience.This is a notion born of eighteenth-century epistemology that still pervadestextbook treatments of both informative and persuasive speeches and is espe-cially prevalent in treatments of informing.

Arrangement advice substitutes for inventional guidance in other ways. Somepublic speaking textbooks substitute variety for diagnosis. They discuss informa-tive speeches of definition or of demonstration, and then offer a wide array ofrhetorical forms that one could use to define or to demonstrate. With respect todefining, for example, DeVito (1990) lists a variety of methods: etymology,authority, operationalization, or symbolization (pp. 221-223). Similarly, Nelsonand Pearson (1990) list definitional devices such as comparison, contrast,synonyms, antonyms, etymology, differentiation, operational definition, andexperiential definition. Again, students are being encouraged to arrange theirmaterial before they have considered systematically why the material may bedifficult to follow.

Yet another example of arrangement advice replacing inventional guidanceinvolves locking students into certain organizational forms without helpingthem think about whether these forms will alleviate confusions. For example,Lucas (1992) lists the following types of informative speeches: speeches aboutobjects, processes, events, and concepts. But Lucas subdivides this classificationand offers arrangement advice for each sub-category. So, within speeches aboutobjects, there are speeches about subjects (people) or objects, and one can speakeither about the history of a subject or about its main features. In the firstinstance, the speech is chronologically ordered. In the second instance, it isspatially ordered. There are two problems with this approach. First, no one inthe real world has the goal of speaking chronologically or spatially. These areforms, not goals. The speaker's goal is to teach or deepen understanding.Second, substituting arrangement for invention fails to assist students in consid-ering why audiences might not understand some information. For instance, onesample speech outlined by Lucas is designed to inform the audience about themajor tenets of Islam. Lucas writes that this speech is effectively presented byidentifying the major elements of the religion and then illustrating each element(p. 288). The problem here is that, again, there is no discussion of why anaudience might not understand the key points. Why might an audience of U.S.college students have trouble in this case? An obstacle is likely to be the

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presumption that Islam is entirely different from Christianity or Judaism, thereligions more familiar to many U.S. students. If that obstacle analysis is correct,then perhaps the speaker could help the audience overcome this difficulty bycomparing the tenets of Islam and Christianity. Ultimately, the expositoryforms, comparison or analogy, may be used as a way of assisting the audience inunderstanding Islam, but they should be discussed after an analysis of why thegoal of explaining the religion's tenets might fail, not before. This considerationof strategy makes the teaching of informative speaking more interesting thanthe form-focused approach.

A third problem results from the idea that informing equals arrangement.This implicit notion makes the steps to informative speaking seem obvious andtherefore unworthy of further study. Such beliefs may discourage authors ofpublic speaking textbooks from gathering new research on strategies for explain-ing difficult ideas.3 Such research exists in abundance. In the last severaldecades, educational research has made impressive headway in identifyingmultiple bases for determining why ideas are difficult to understand. This workmay be found in fields such as concept learning or instructional design,educational psychology, science education, and related areas (for reviews, seeRowan, 1988, 1992; Shymansky & Kyle, 1988). These fields offer lines of inquiryand important findings relevant to informative speakers.

In sum, current pedagogy for informative speaking implicitly rests on anoutdated epistemology, creates confusion about the purposes of informativespeaking, is essentially nonstrategic, and generally fails to familiarize studentswith research relevant to explaining ideas well. There are good reasons then forexploring alternative approaches. The ideal pedagogy should be (a) definition-ally clear and focused on speakers' purposes or functions when informing, (b)useful in diagnosing likely audience confusions with some topic, and (c) helpfulin guiding speakers to empirically supported techniques for overcoming confu-sion. In the following section, I present an alternative pedagogy designed tomeet these criteria.

AN ALTERNATE PEDAGOGY

Explanatory speaking may be defined by drawing from Kinneavy's Theory ofDiscourse (1971). He classifies all discourse by inferable authorial aim (see Figure1) and identifies four types of discursive aim: self-expression, persuasion,reference, and literary.4 Reference refers to discourse where communicatorschiefly represent some aspect of reality, rather than persuading, expressingthemselves, or creating literary artifacts. For Kinneavy, expository speech is oneform of reference discourse (see figure 1).

Kinneavy divides reference discourse into three sub-types by locating morespecific authorial goals: scientific, exploratory, and informative. Scientific orscholarly discourse represents some aspect of reality by proving claims about it(scholarly papers and presentations are instances). Exploratory discourse (specu-lative essays) represents an aspect of reality by questioning accepted notions.Informative discourse, found in news reports, textbooks, teachers' lectures,popular magazines, and encyclopedias, represents reality by making informa-tion accessible to lay audiences.

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Discursive Aims

ELEMENT

GOALS

Speaker

Self-expressive

Audience

Persuasive

Reality or World

Reference

TYPES OFREFERENCE I

Exploratory

Language

Literary

Informative ScientificI

Representative

TYPES OFINFORMATIVE

TYPES OFEXPLANATORY

Explanatory Informatory

Transformative Quasi-Scientific Elucidating

FIGURE 1

A THEORY OF EXPLANATORY DISCOURSE BUILT FROM K I N N E A V Y ' S ( 1 9 7 1 ) THEORY OF DISCURSIVE AIMS. A VERSION

OF THIS DIAGRAM APPEARS IN ROWAM ( 1 9 8 8 ) .

Notions of expository discourse can be further refined. Following Kinneavy'slogic, Rowan (1988) suggested dividing informative discourse into two sub-types. Informatory presentations create awareness of the latest information aboutsome topic. A news report on the latest fighting between the Serbs and theCroatians would be informatory. In contrast, explanatory presentations enhanceunderstanding of phenomena about which we are aware but do not fullyunderstand. A presentation on why the Serbs and Croats are historical enemieswould be explanatory. To illustrate further: a university's schedule of classes isinformatory; an account of how to register for these classes is explanatory. Apresentation on the latest graphics software available for DOS machines couldbe informatory (if it focused on awareness-creation more than on gaining sales);a presentation on why laser printing a graphic is more complex than printingtext would be explanatory. When we teach informative speaking, we usuallywant explanatory, not informatory discourse. News reports are informatory. Ina classroom setting, we generally want students to deepen our understanding ofsome phenomenon or aid us in mastering some skill. Generally, we do notassume they are in a position to provide classmates the "latest" informationabout some topic. Consequently, my focus is on pedagogy for explanatorydiscourse.

Good explanatory speeches are frequently those that address questions of"how," "why," or "what does that mean?" Paradigmatic instances of students'explanatory speeches include answers to questions such as: How do locks and

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keys work? Why do people yawn? What are modern artists trying to achieve?How do we get our drinking water? Why is irradiated food healthful? What's thedifference between stocks and bonds? The challenge for explanatory speakers isto classify the principal sort of difficulty their audience will face for a particulartopic and then to shape their speech so as to overcome that difficulty.

METHODS FOR OVERCOMING CONFUSION

There are three chief difficulties in understanding complex ideas (Rowan, 1988,1990, 1992). An idea may be difficult or confusing because it involves (a) difficultconcepts or language, (b) difficult-to-envision structures or processes, or (c) notions thatare difficult to understand because they are hard to believe (e.g., the Earth is weight-less). Scholars in educational research have explored each of these obstacles tounderstanding by identifying effective techniques at overcoming each (e.g.,Brown, 1992; Hewson & Hewson, 1983, 1984; Hynd & Alvermann, 1986;Mayer, 1983, 1989; Mayer & Anderson, 1992; Merrill & Tennyson, 1977;Shymansky & Kyle, 1988; Tennyson & Cocchiarella, 1986; Watts & Pope, 1989).Efforts to overcome each of these difficulties constitute a characteristic type ofexplanation. There are elucidating explanations which clarify the meaning and useof terms, quasi-scientific explanations which help audiences mentally model com-plex phenomena, and transformative explanations which help people understandcounter-intuitive or implausible ideas.

Following are discussions of the above explanation types including the fea-tures most likely to make them effective. Just as a theory of "causes of disease"helps contemporary physicians classify, diagnose, and implement appropriatecurative strategies, knowledge of the principal types of confusion that audiencesexperience can help explanatory speakers anticipate an audience's difficulties inunderstanding complex ideas.

ELUCIDATING EXPLANATIONS

If the audience's chief difficulty rests in mastering the meaning and use of acertain term, then the strategy governing a speaker's presentation should bethat of an elucidating explanation. Elucidating explanations illuminate a concept'smeaning and use. For example, speakers principally concerned with explainingnotions such as the difference between validity and reliability, the meaning ofliberation theology, or why corals are classified as animals and not plants, shoulduse elucidating explanations.

Research in instructional design and linguistics shows that when people arestruggling to understand the meaning or the use of a term, they are in factstruggling to distinguish a concept's essential (always present) from its associated(frequent but not necessary) features (Merrill & Tennyson, 1977; Tennyson &Cocchiarella, 1986). Thus, good elucidating explanations focus attention on thisdistinction. Specifically, researchers in instructional design have found thatgood elucidating explanations contain (a) a typical exemplar of the concept, (b) adefinition that lists a concept's essential features, (c) an array of varied examplesand nonexamples (nonexamples are instances likely to be mistaken for examples),and (d) opportunities to practice distinguishing examples from nonexamples bylooking for essential features (Merrill & Tennyson, 1977; Tennyson & Cocchi-arella, 1986).

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Because good elucidating explanations include sets of varying examples andnonexamples as well as definitions, they are more effective at emphasizing aconcept's critical features than definitions alone. That is, concept mastery occurswhen people consider a concept's application to an array of varying instancesand practice distinguishing examples of the concept from tempting nonex-amples. Or, they listen to a presentation that explores these distinctions.

For example, one student, who had worked at a nuclear power plant, gave aspeech explaining radiation. He noted that many people think radiation isalways bad or dangerous. They believe "dangerous" is an essential qualifierassociated with all instances of radiation. The Associated Press Stylebook (French,Powell, & Angione, 1992) defines radiation as "invisible particles or waves givenoff by radioactive material, such as uranium. Radiation can damage or kill bodycells, resulting in genetic damage or death" (p. 140). The term radiation,however, generally refers to electromagnetic radiation, which includes "every-thing from kilometers-long radio waves to tiny x-rays and gamma rays. . . .Radiation can refer to the electromagnetic radiation emitted by a candle flameor the subatomic particles emitted by uranium ore" (Mims, 1992, p. 101). Thus,radiation includes sunlight, energy from light bulbs, televisions, computers,electrical wires, and many other ubiquitous phenomena. The speaker con-cluded that "dangerous" is not an essential feature of radiation's meaning eventhough exposure to certain types of radiation may be dangerous (danger beingdetermined by the radiation source, the intensity of that source, and theduration of exposure). By offering an array of examples and by demonstratingthat "danger" was an associated meaning of radiation and not an essential one,the speaker assisted his audience in developing a more accurate conception ofthis much used, but often misunderstood, concept.

QUASI-SCIENTIFIC EXPLANATIONS

If an idea is difficult chiefly because complexity obscures its main points, thenspeakers should present a quasi-scientific explanation. Just as scientists try todevelop models of the world, quasi-scientific explanations model or picture thekey dimensions of some phenomenon for lay audiences. Speakers presentingdifficult-to-envision topics such as how radar works, the structure of the U.S.federal court system, the similarities and differences between Islam and Chris-tianity, or how DNA molecules pass on genetic information, should use quasi-scientific explanations.

Perhaps because the chief difficulties in adequately modeling complex phe-nomena lie in locating their key components or processes, good quasi-scientificexplanations have easily discernible main points and clear connections amongthem. Specifically, researchers in educational psychology (e.g., Mayer, 1983,1989; Mayer & Andersen, 1992; Mayer, Dyck, & Cook, 1984) have found thateffective quasi-scientific explanations contain features that highlight the struc-ture of the phenomenon being explained and essentially overcome two obstaclesto comprehension: difficulties in getting a general impression of some phenom-enon and difficulties in conceptualizing that phenomenon's parts, processes,and interrelations. Current informative speaking pedagogy is useful in helpingstudents consider these obstacles to understanding (e.g., De Vito, 1990; Verder-ber, 1994).

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The difficulty of not having the "big picture" is best overcome through devicesthat quickly convey structure or gist. These include graphic features such assimplified drawings, cartoons, videos, and models of all sorts (Gilbert & Osborne,1980; Mayer & Anderson, 1992; Robins & Mayer, 1993). Verbal strategies arealso helpful. Some effective strategies include structure-suggesting titles ("Green-house Earth" or "Five Areas of Study"), organizing analogies (e.g., "Your brainworks like a computer"), and model-suggesting topic sentences (e.g., "Radar workslike an echo" or "Islam is similar to Christianity in some ways and different inothers") (See Loman and Mayer, 1983, Mayer, 1985a, Mayer 1985b, and Mayer,Dyck, and Cook, 1984).

The second difficulty good quasi-scientific explanations must overcome is thatof helping listeners see the relationships among a phenomenon's sub-components or sub-processes. Transitional phrases, previews, summaries, andexplicit statements of relationships all aid people in refining their mental modelsof some subject (Loman & Mayer, 1983; Mayer, Dyck, & Cook, 1984). Interest-ingly, research has shown that over-use of short sentences can actually harmpeople's abilities to see connections among ideas, particularly when sentencesare arbitrarily shortened for shortness' sake. In some cases, important linkingwords such as "because" and "for example" are cut from sentences in themistaken belief that short sentences inevitably enhance comprehension (Davi-son, 1984).

One text feature that helps people see relationships among complex ideas isthat of continually re-invoking initial comparisons. This technique facilitatesmapping old knowledge onto the new. We see interrelations among sub-components illuminated in Gentner's (1988) analysis of Rutherford's analogycomparing the hydrogen atom to the solar system. As Gentner notes, thisanalogy facilitates learning because of its high systematicity. Rutherford went onto show how his analogy held among sub-components of both systems: thenucleus in the atom is like the sun in the solar system, the electrons like planets,the attractive forces between the atom's nucleus and electrons like those be-tween the sun and its planets. Similarly, a good quasi-scientific presentation onhow human vision works could compare an eye's parts with those of a camera.Links may be made between the relation of the pupil to the retina with that ofthe aperture adjustment to film.

Another good quasi-scientific speech might explain how radar works. Usingan organizing analogy, the speaker could say that radar works essentially theway an echo does, except that radio, rather than sound waves, are sent andreceived. The speaker could refer to the echo analogy as she points to a visualaid and discusses the radar signal's transmission (similar to shouting in acanyon) and reception (similar to hearing the echo).

TRANSFORMATIVE EXPLANATIONS

If the chief source of difficulty is neither a confusing term nor a complex mass ofinformation, but is rather the counter-intuitivity of an idea, then speakers coulddesign their talks as transformative explanations. For example, the idea that when aperson pushes on a concrete wall, that wall exerts an equal and opposite force(Newton's Third Law of Motion) contains no difficult terms, but from a layperspective, it may seem implausible. Transformative explanations are designed

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to present such counter-intuitive ideas by helping lay audiences transform theireveryday "theories" of phenomena into more accepted notions. Questions bestanswered with transformative presentations might include: why natural foodssuch as potatoes contain dangerous toxins, how men can get breast cancer, whybelief in a just world leads people to blame victims for their plights, or whyabstract art can be more technically and intellectually demanding than portrai-ture.

Educational research shows that people's chief difficulties in understandingcounter-intuitive ideas lie in understanding why their own, implicit theory isinadequate (Brown, 1992; Hewson & Hewson, 1983; Shymansky & Kyle, 1988;Watts & Pope, 1989). Thus, good transformative explanations begin by discuss-ing the audience's implicit theory first and then demonstrating its limitations(Anderson & Smith, 1984; Hewson & Hewson, 1983; Hynd & Alvermann, 1986;Rowan, 1991). Specifically, science educators have found that the best transfor-mative explanations are those that (a) state people's "implicit" or "lay" theoryabout the phenomenon or ask questions that elicit this theory, (b) acknowledgethe apparent plausibility of the lay theory, (c) reject the lay theory and demon-strate its inadequacy with examples familiar to the audience, and (d) state themore accepted account and illustrate its greater effectiveness.

In one of my classes, several students developed a transformative explana-tion—aimed at nonscience students—for why otherwise healthful foods containnatural toxins. Here are the principal components ofthat account. The studentsused Ames, Magaw, and Gold (1987) to inform their explanatory efforts.

[State lay theory]. It seems reasonable—no, OBVIOUS—to believe that when we eat healthfulfoods we are ingesting substances that are good for us.

[Acknowledge the apparent plausibility of the lay theory, but then reject it and illustrate its inadequacy bylocating contradictory examples familiar to the audience.] There are many good reasons for believing"natural foods" are good for us. Clearly, eating healthful food is associated with well-being.Many long-lived people are known for their healthful eating. Personal experience tells us we feelbetter when we have a balanced diet. However, it is not the case that all things natural arehealthful. We know that some snakes are poisonous, that forests contain poison ivy, and thatsimply eating too much food—however natural—is bad for us. So, perhaps we should not be toosurprised to learn that healthful foods such as fresh baked bread, shrimp, potatoes, and peanutsoften contain naturally created toxins, pesticides, and human carcinogens.

[Demonstrate the adequacy of the more orthodox view]. Why would natural toxins exist in foods?Plants develop these toxins to protect themselves from fungi, insects, and predators. Accordingto Bruce Ames, a biochemist at the University of California, Berkeley, and his associates, naturalcarcinogens may be more responsible for human cancers than synthetic chemicals. As thesescientists say, "We are ingesting in our diet at least 10,000 times more by weight of naturalpesticides than of manmade pesticide residues" (Ames et al., 1987, p. 272).

For example, one human carcinogen is aflatoxin. Aflatoxin is a natural toxin that contami-nates wheat, corn, nuts, and stored carbohydrate foods like peanut butter. Aflatoxin is alsofound in the milk of cows that eat moldy grain.

As Ames et al. write, "We . . . are almost completely ignorant of the carcinogenic potential ofthe enormous background of natural chemicals in the world. For example cholinesteraseinhibitors are a common class of pesticides, both man-made and natural. Solanine andchaconine (the main alkaloids in potatoes) are cholinesterase inhibitors and were introducedinto the human diet about 400 years ago with the dissemination of the potato from theAndes. . . . Neither alkaloid has been tested for carcinogenicity. . . ." (p. 277).

In essence, the idea that natural foods are entirely healthful is not a sound one. There are avariety of forces in nature, not all of which are beneficial to human health. Plants' need to survivecauses them to develop defense systems, some of which are harmful to humans. Further,

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because cancers usually take a long time to kill, evolution may not have helped us developdefenses against them. We may be biologically better equipped to avoid acute hazards than weare chronic dangers that manifest themselves past usual reproductive ages.

As this example shows, the key to good transformative explanation is recogniz-ing that when people have deeply held implicit theories, they do not reject theirtheories easily. Implicit theories exist because they seem to work. Good transfor-mative explanations do not simply reject them. Instead, these explanationsremind audiences that their implicit theories do not account for phenomenawith which they themselves are familiar.

After considering this "natural carcinogens" example, one might wonder iftransformative explanations are appropriate only for natural science topics. Butwhile there are many non-intuitive scientific notions, counter-intuitive notionsare not exclusively scientific. People develop powerful but tacit lay theoriesabout familiar dimensions of life (e.g., art and race relations as well as nutritionand disease). In fact, communication teachers often generate good transforma-tive explanations while lecturing on the notion that perception is a subjective,rather than an objective, process. Instructors are aware that simply asserting thesubjective and constructive character of perception would not be effective.Consequently, they usually begin lectures by acknowledging the apparentplausibility of the "objective-perception hypothesis." They tell students that it isnatural to assume that what is perceived is exactly correspondent to reality. Butthen the inadequacy of the objective-perception hypothesis is demonstrated byusing optical illusions or attribution exercises, showing that the mind partlycreates the reality it perceives. Only after these exercises, do instructors assertand explain the subjectivity of perception.

IMPLICATIONS OF THE PEDAGOGYThis alternative approach to the teaching of explanatory speaking improvesinstruction in several ways. First, it improves teaching by giving it a moreanalytic, more reasoned approach. Novice public speaking instructors tend totranslate instruction in informative speaking into lists of requirements for form.According to some novices, a good informative speech has an introduction, abody with at least two main points, a summary conclusion, at least one visual aid,and a subject of interest to the audience. Of course, such an approach is formrather than function focused. It fails to give students practice in analyzing theconceptual challenges an audience might face in listening to a complex presen-tation.

This alternative pedagogy encourages thinking. Students assigned explana-tory speeches first consider several topics that their classmates would like tolearn and the principal reasons for any difficulty in understanding the subject.Toward this end, speakers interview class members. Then they produce strate-gic analyses, noting what conceptual difficulties audience members have withtheir topics. Next, they conduct research on their topics and eventually generatespeech outlines using the explanation type that best overcomes these difficulties.Student speeches developed in this manner are frequently well-reasoned andfun.

Additionally, having a theory of explanatory discourse makes lecturing andtutorial explanation more intellectually stimulating. Having a theoretical basisfor considering why, for example, students have difficulty mastering some

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apparently mundane distinction (e.g., the difference between independent anddependent clauses) makes the task of explaining more of a challenge. Regardlessof whether the explanation succeeds or fails, teachers can attempt to determinethe reason for its effect on the audience.

The proposed theory of explanatory discourse may also have importantbenefits for teacher training. First, it may encourage reflection in lesson plan-ning, lecturing, and text selection. Second, the theory may especially helpnovice teachers with course material planning. In reviewing the content for agiven class, novice teachers could be trained to anticipate and minimize likelydifficulties that their students may face in mastering certain material. Theycould produce brief strategy analyses that require them to draw from theappropriate techniques discussed earlier (e.g., an extended elucidating, quasi-scientific, or transformative explanation).

Finally, the proposed theory can be presented as a heuristic device tostudents; that is, it can function as a way of checking comprehension of lectureor textual explanations. It can serve also as a basis for re-thinking or challengingsuch materials. For example, one may envision a communication class session onthe definition of mass communication. Frequently such exercises are teacher-dominated. Students taught to analyze definitions as elucidating explanationsmay be better able to engage in or critique a teacher's definitional claims. Forinstance, some definitions of mass communication insist that all instances of thisphenomenon must be directed to mass audiences. A student may object,though, and ask whether telephone conversations used in telemarketing countas instances of mass communication. The student could argue that telemarket-ing allows access to mass audiences even though the members of such audiencesare contacted individually. Learning that one tests definitions by generating arange of instantiating examples can assist students in considering definitionalclaims. Additionally, knowledge of the features of good quasi-scientific andtransformative explanations should help them check their understanding ofcomplex structures and processes.

CONCLUSION

Eighteenth-century rhetoricians such as Campbell believed the human mindreasons by certain universal patterns. Placing information in these patterns(e.g., by chronology, causal order) therefore seemed the key step in makinginformation clear. In twentieth-century public speaking textbooks, we still seesimilar treatments of informative speaking, treatments that equate the goal ofinforming with matters of arrangement. When informing is equated witharrangement, however, students are discouraged from actively considering anaudience's likely difficulties in understanding complex subject matter. In addi-tion, the false notion that informing is an uninteresting and "obvious" process isencouraged. Unfortunately, this false notion still pervades pedagogy and makeseven our best public speaking textbooks less effective.

This essay offers a new, invention-emphasizing pedagogy for explanatoryspeaking. This pedagogy is supported by classical rhetoric's emphasis on inven-tion and by decades of contemporary educational research on sources ofintellectual confusion and methods for addressing them. In essence, it trans-forms the process of explaining difficult ideas into an explicitly strategic enter-prise for which there is important traditional and recent empirical guidance.

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Just as discovering the causes of infectious diseases improved physicians' diag-nostic capabilities, so too can discovering causes of confusion assist explanatoryspeakers. Since the fifth century BC, rhetorical training has aided speakers indiscerning the available means of persuasion. This pedagogy provides similarguidance to those explaining difficult ideas.

NOTES1To identify prevalent ways of teaching informative speaking for this essay, I located six recent, top-selling

public speaking textbooks that have at least one chapter devoted to informative speaking. I reviewed theinformative speaking chapters in these textbooks carefully and examined their coverage of other topics relevantto informing, such as advice on research, audience analysis, forms of support, visual aids, and language choice. Iselected textbooks for this analysis that focused on the teaching of public speaking, rather than on othercommunication subject matter. These contemporary texts were: Beebe and Beebe (1994), DeVito (1990), Lucas(1992), Nelson and Pearson (1990), Osborn and Osborn (1994), and Verderber (1994). In addition, I examinedtwo editions of a textbook first issued in the 1930s: Monroe (1945) and Monroe and Ehninger (1969). Theselatter textbooks were reviewed to see if pedagogy for informative speaking had changed substantially in the lastfew decades. It has not.

2Several of the eight textbooks I examined include sections on the speech to explain a difficult idea. These areLucas (1992), Nelson and Pearson (1990) and Osborn and Osborn (1994). Each gives good advice; emphasis isplaced, however, on the use of rhetorical forms for explaining, rather than on offering inventional guidance toassist speakers in anticipating likely confusions.

3Several contemporary public speaking textbooks offer some discussion of contemporary educationalresearch relevant to informative speaking. For example, Lucas (1992) discusses research from educationalpsychology on the role of visual aids in assisting learning. For their discussion of informative speaking Nelsonand Pearson (1990) draw from research on learning and memory. In addition, Osborn and Osborn (1994) citemy integrations of rhetorical theory with educational research (e.g., Rowan, 1988, 1990) in their treatment ofthe speech to explain. For the most part, though, this research appears sporadically in contemporary publicspeaking textbooks. It does not inform systematic inquiry about obstacles to understanding complex subjectmatter.

4Note that Kinneavy (1971) takes the position that there are at least four fundamental communication goals.From his perspective, then, one kind of communication is principally persuasive, but not all kinds. Others arguethat all communication efforts are persuasive. For instance, in their public speaking textbook, Nadeau,Jablonski, & Gardner, (1993) write that "all talks, presentations, speeches, discourses, lectures, sermons, orreports are fundamentally persuasive. The persuasive component of the speaker's e thos . . . is ever present evenin a mathematics class" (p. 157). A third perspective is that claims about fundamental types of discourse are notontological but rather interpretive. That is, those taking this third position would say it is sometimes useful toanalyze discourse as though it is entirely persuasive, or self-expressive, or informative, or literary. On the otherhand, it is sometimes useful to analyze discourse as though multiple aims are pursuable in most contexts whilethe dominant aim in a given case can be persuasion, or understanding, or entertainment, or self-expression.Critics can make judgments about the dominant aim animating a given text by assessing features of the text andits context. Subscribing to this last view, I argue, as Kinneavy does, that it is illuminating to maintain that somediscourse is more oriented toward deepening understanding (e.g., teaching) than it is toward gainingagreement (e.g., selling). But whether one sees aims in discourse as phenomena that differ in degree or kind, theessential argument of this essay is that there is as much exciting strategy involved in explaining somethingdifficult as there is in gaining agreement. Consequently, speech communication textbooks should do more toassist speakers with the former kind of strategizing.

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