3.3: Using Support to Strengthen Your Persuasive Speech

Learning Objectives

1. Understand the three reasons we use support in speeches.
2. Explain four criteria used to evaluate support options.
3. Differentiate between different types of support that can be used in Persuasive Speeches

 

Figure \(\PageIndex{1}\): Support (CC BY-NC-ND 2.0; Pixel Fantasy via Flickr)

In persuasive speaking, the word “support” refers to a range of strategies that are used to develop the central idea and specific purpose by providing corroborating evidence. Using support helps you create a more substantive and polished speech. We sometimes use the words “support” or “evidence” synonymously or interchangeably because both are designed to help ground your persuasive speech.

Why We Use Support

Speakers use support to help provide a foundation for their message. You can think of support as the legs on a table. Without the legs, the table becomes a slab of wood or glass lying on the ground; as such, it cannot fully serve the purpose of a table. In the same way, without support, a speech is nothing more than fluff. Audience members may ignore the speech’s message, dismissing it as just so much hot air. In addition to being the foundation that a speech stands on, support also helps us clarify content, increase speaker credibility, and make the speech more vivid.

To Clarify Content

The first reason to use support in a speech is to clarify content. Speakers often choose a piece of support because a previous writer or speaker has phrased something in a way that evokes a clear mental picture of the point they want to make. For example, suppose you’re preparing a speech about hazing in college fraternities. You may read your school’s code of student conduct to find out how your campus defines hazing. You could use this definition to make sure your audience understands what hazing is and what types of behaviors your campus identifies as hazing.

To Add Vividness

In addition to clarifying content and enhancing credibility, support helps make a speech more vivid. Vividness refers to a speaker’s ability to present information in a striking, exciting manner. The goal of vividness is to make your speech more memorable. One of the authors still remembers a vivid example from a student speech given several years ago. The student was speaking about the importance of wearing seat belts and stated that the impact from hitting a windshield at just twenty miles per hour without a seat belt would be equivalent to falling out of the window of their second-floor classroom and landing face-first on the pavement below. Because they were in that classroom several times each week, students were easily able to visualize the speaker’s analogy and it was successful at creating an image that is remembered years later. Support helps make your speech more interesting and memorable to an audience member.

To Add Credibility

Another important reason to use support is that it adds to your credibility as a speaker. The less an audience perceives you as an expert on a given topic, the more important it is to use a range of support. By doing so, you let your audience know that you’ve done your homework on the topic.

At the same time, you could hurt your credibility if you use inadequate support or support from questionable sources. Your credibility will also suffer if you distort the intent of a source to try to force it to support a point that the previous author did not address. For example, the famous 1798 publication by Thomas Malthus, An Essay on the Principle of Population, has been used as support for various arguments far beyond what Malthus could have intended. Malthus’s thesis was that as the human population increases at a greater rate than food production, societies will go to war over scarce food resources (Malthus, 1798). Some modern writers have suggested that, according to the Malthusian line of thinking, almost anything that leads to a food shortage could lead to nuclear war. For example, better health care leads to longer life spans, which leads to an increased need for food, leading to food shortages, which lead to nuclear war. Clearly, this argument makes some giant leaps of logic that would be hard for an audience to accept.

Evaluating Support

It is important to evaluate your support to ensure that it will not detract from your credibility as a speaker. Here are four characteristics to evaluate when looking at support options: accuracy, authority, currency, and objectivity.

Accuracy

One of the quickest ways to lose credibility in the eyes of your audience is to use support that is inaccurate or even questionably accurate. Admittedly, determining the accuracy of support can be difficult if you are not an expert in a given area, but here are some questions to ask yourself to help assess a source’s accuracy:

• Does the information within one piece of supporting evidence completely contradict other supporting evidence you’ve seen?
• If the support is using a statistic, does the supporting evidence explain where that statistic came from and how it was determined?
• Does the logic behind the support make sense?

One of this book’s authors recently observed a speech in which a student said, “The amount of pollution produced by using paper towels instead of hand dryers is equivalent to driving a car from the East Coast to St. Louis.” The other students in the class, as well as the instructor, recognized that this information sounded wrong and asked questions about the information source, the amount of time it would take to produce this much pollution, and the number of hand dryers used. The audience demonstrated strong listening skills by questioning the information, but the speaker lost credibility by being unable to answer their questions.

Authority

The second way to use support in building your credibility is to cite authoritative sources—those who are experts on the topic. In today’s world, there are all kinds of people who call themselves “experts” on a range of topics. There are even books that tell you how to get people to regard you as an expert in a given industry (Lizotte, 2007). Today there are “experts” on every street corner or website spouting off information that some listeners will view as legitimate.

So what truly makes someone an expert? Bruce D. Weinstein, a professor at West Virginia University’s Center for Health Ethics and Law, defined expertise as having two senses. In his definition, the first sense of expertise is “knowledge in or about a particular field, and statements about it generally take the form, ‘S is an expert in or about D.’… The second sense of expertise refers to domains of demonstrable skills, and statements about it generally take the form, ‘S is an expert at skill D (Weinstein, 1993).’” Thus, to be an expert, someone needs to have considerable knowledge on a topic or considerable skill in accomplishing something.

As a novice researcher, how can you determine whether an individual is truly an expert? Unfortunately, there is no clear-cut way to wade through the masses of “experts” and determine each one’s legitimacy quickly. However, Table 8.1 “Who Is an Expert?” presents a list of questions based on the research of Marie-Line Germain that you can ask yourself to help determine whether someone is an expert (Germain, 2006).

Table 8.1 Who Is an Expert?

Questions to Ask Yourself	Yes	No
1. Is the person widely recognizable as an expert?
2. Does the person have an appropriate degree/training/certification to make her or him an expert?
3. Is the person a member of a recognized profession in her or his claimed area of expertise?
4. Has the person published articles or books (not self-published) on the claimed area of expertise?
5. Does the person have appropriate experience in her or his claimed area of expertise?
6. Does the person have clear knowledge about her or his claimed area of expertise?
7. Is the person clearly knowledgeable about the field related to her or his claimed area of expertise?
8. When all is said and done, does the person truly have the qualifications to be considered an expert in her or his claimed area of expertise?

You don’t have to answer “yes” to all the preceding questions to conclude that a source is credible, but a string of “no” answers should be a warning signal. In a Columbia Journalism Review article, Allisa Quart raised the question of expert credibility regarding the sensitive subject of autism. Specifically, Quart questioned whether the celebrity spokesperson and autism advocate Jennifer McCarthy (www.generationrescue.org/) qualifies as an expert. Quart notes that McCarthy “insists that vaccines caused her son’s neurological disorder, a claim that has near-zero support in scientific literature” (Quart, 2010). Providing an opposing view is a widely read blog called Respectful Insolence, whose author is allegedly a surgeon/scientist who often speaks out about autism and “antivaccination lunacy.” Respectful Insolence received the 2008 Best Weblog Award from MedGagdet: The Internet Journal of Emerging Medical Technologies. We used the word “allegedly” when referring to the author of Respectful Insolence because as the website explains that the author’s name, Orac, is the “nom de blog of a (not so) humble pseudonymous surgeon/scientist with an ego just big enough to delude himself that someone, somewhere might actually give a rodent’s posterior about his miscellaneous verbal meanderings, but just barely small enough to admit to himself that few will” (ScienceBlogs LLC).

When comparing the celebrity Jenny McCarthy to the blogger Orac, who do you think is the better expert? Were you able to answer “yes” to the questions in Table 8.1 “Who Is an Expert?” for both “experts”? If not, why not? Overall, determining the authority of support is clearly a complicated task, and one that you should spend time thinking about as you prepare the support for your speech.

Currency

The third consideration in using support to build your credibility is how current the information is. Some ideas stay fairly consistent over time, like the date of the Japanese attack on Pearl Harbor or the mathematical formula for finding the area of a circle, but other ideas change wildly in a short period of time, including ideas about technology, health treatments, and laws.

Although we never want to discount classic supporting information that has withstood the test of time, as a general rule for most topics, we recommend that information be less than five years old. Obviously, this is just a general guideline and can change depending on the topic. If you’re giving a speech on the history of mining in West Virginia, then you may use support from sources that are much older. However, if you’re discussing a medical topic, then your support information should probably be from the past five years or less. Some industries change even faster, so the best support may come from the past month. For example, if are speaking about advances in word processing, using information about Microsoft Word from 2003 would be woefully out-of-date because two upgrades have been released since 2003 (2007 and 2010). As a credible speaker, it is your responsibility to give your audience up-to-date information.

Objectivity

The last question you should ask yourself when examining support is whether the person or organization behind the information is objective or biased. Bias refers to a predisposition or preconception of a topic that prevents impartiality. Although there is a certain logic to the view that every one of us is innately biased, as a credible speaker, you want to avoid just passing along someone’s unfounded bias in your speech. Ideally you would use support that is unbiased; Table 8.2 “Is a Potential Source of Support Biased?” provides some questions to ask yourself when evaluating a potential piece of support to detect bias.

Table 8.2 Is a Potential Source of Support Biased?

Questions to Ask Yourself	Yes	No
1. Does the source represent an individual’s, an organization’s, or another group’s viewpoint?
2. Does the source sound unfair in its judgment, either for or against a specific topic?
3. Does the source sound like personal prejudices, opinions, or thoughts?
4. Does the source exist only on a website (i.e., not in print or any other format)?
5. Is the information published or posted anonymously or pseudonymously?
6. Does the source have any political or financial interests related to the information being disseminated?
7. Does the source demonstrate any specific political orientation, religious affiliation, or other ideology?
8. Does the source’s viewpoint differ from all other information you’ve read?

As with the questions in Table 8.1 “Who Is an Expert?” about expertise, you don’t have to have all “no” or “yes” responses to decide on bias. However, being aware of the possibility of bias and where your audience might see bias will help you to select the best possible support to include in your speech.

Types of Support \(\PageIndex{1}\)

1. Facts and statistics: Facts are truths established through evidence or scientific process, often used by speakers to inform an audience. Many facts are underpinned by statistics, the mathematical field for collecting, analyzing, and inferring from data. Facts and statistics are useful to reinforce or demonstrate information. Unfortunately, many speakers and audience members do not have a strong mathematical background, so it is important to understand the statistics used and communicate this information to the audience.
2. Definitions: Effective communication requires shared understanding. Speakers often use definitions to clarify words or ideas, ensuring the audience is "on the same page." There are four main types of definitions used as support. Lexical definitions state how a word is used within a given language. Persuasive definitions are devised to express a word or term in a specific persuasive manner. Stipulative definitions are created when a word or term is coined. Theoretical definitions attempt to describe all parts related to a particular type of idea or object. The key to using definitions effectively is to strike a balance: define terms when necessary to enhance understanding, but avoid defining what your audience already knows to prevent appearing condescending or wasting time.
3. Examples: Examples are specific situations, problems, or stories that help illustrate an idea or phenomenon, making abstract concepts more concrete. Positive examples are used to clarify or clearly illustrate a principle, method, or phenomenon. Negative examples show how not to behave in a specific situation. Nonexamples are used to express what something is not. Best examples show the best way someone should behave in a situation. While powerful for illustration, examples can be dismissed as unusual cases by some audience members. Therefore, ensure your examples are relevant and resonate with your audience's broader understanding.
4. Narratives: Narratives, or stories, are another potent form of support that engage audiences on a deeper level. Humans are naturally drawn to stories, which provide a clear arc (beginning, middle, end) to help listeners understand a message. Informative narratives provide information or explanations about a speaker’s topic. Persuasive narratives are stories a speaker can use to get his or her audience to accept or reject a specific attitude, value, belief, or behavior. Entertaining narratives are stories that are designed purely to delight an audience. Speakers have an ethical obligation to let the audience know whether a narrative is true or hypothetical.
5. Testimonies: Testimony provides support through expert opinion or direct accounts from witnesses. Expert testimony is an account given by someone who is a recognized expert on a given topic. Eyewitness testimony is an account given by an individual who has had firsthand experience with a specific phenomenon or idea. Explaining the context of the testimony is important so your audience can evaluate the likelihood that the testimony is accurate, current, and unbiased.
6. Analogy: An analogy compares two ideas or objects to show how they are similar, implying further similarities that support your argument. Figurative analogies compare two ideas or objects from two different classes. Conversely, literal analogies compare two objects or ideas that clearly belong to the same class. Speakers using analogies need to make sure that the audience will be able to see the similarity between the objects or ideas being compared.

Exercises

1. Look at the speech you are currently preparing for your public speaking class. What types of support are you using? Could you enhance the credibility of your speech by using other types of support? If so, what types of support do you think you are lacking?
2. Find and analyze a newspaper op-ed piece or letter to the editor that takes a position on an issue. Which types of support does the writer use? How effective and convincing do you think the use of support is? Why?
3. You’ve been asked to give a speech on child labor within the United States. Provide a list of possible examples you could use in your speech. You should have one from each of the four categories: positive, negative, non, and best

References

Germain, M. L. (2006). Development and preliminary validation of a psychometric measure of expertise: The generalized expertise measure (GEM). (Unpublished doctoral dissertation). Barry University, Florida.

Lizotte, K. (2007). The expert’s edge: Become the go-to authority people turn to every time. New York, NY: McGraw-Hill.

Malthus, T. R. (1798). An essay on the principle of population as it affects the future improvement of society, with remarks on the speculations of Mr. Godwin, M. Condorcet, and other writers. London, England: J. Johnson, in St. Paul’s Churchyard.

Quart, A. (2010, July/August). The trouble with experts: The web allows us to question authority in new ways. Columbia Journalism Review.

ScienceBlogs LLC (n.d.). Who (or what) is Orac? [Web log post].

Weinstein, B. D. (1993). What is an expert? Theoretical Medicine, 14, 57–93.

Adapted from:

 

LibreTexts. (n.d.). 8.02: Exploring Types of Support. In Stand Up, Speak Out: The Practice and Ethics of Public Speaking (Chapter 08: Supporting Ideas and Building Arguments). Social Sci LibreTexts.