Student Resource
Gamble, The Public Speaking Playbook, 2nd Edition
SAGE Publishing, 2018
Lecture Notes
Chapter 20: Methods of Persuasion
Learning Objectives
1-1 Use sound evidence.
1-2 Apply Toulmin’s Reasonable Argument Model.
1-3 Use deductive, inductive, and causal reasoning, as well as reasoning from analogy.
1-4 Arouse emotion
1-5 Name the three tenets of persuasive speaking
1-6 Avoid common logical fallacies.
1-7 Design and deliver a persuasive speech.
Outline
I. Audience members don’t share the same attitudes or beliefs about controversial
issues.
A. The target audience represents the segment of the actual audience that you
want your message to affect.
1. Speakers should consider the needs, values, concerns, and interests of
the target audience when creating a presentation.
2. Speakers still need to consider the remainder of the audience even
though the target audience is identified.
3. Speakers can strive for creating small changes in audience members
rather than instant conversions.
II. Speakers should learn how to build persuasive credibility.
A. Ethos arguments convince an audience by using a speaker’s credibility or
character.
1. The more credibility that a speaker possesses, the more likely the
audience will listen to what is said.
2. Initial credibility is how the audience perceives you before you speak.
3. A speaker’s derived credibility occurs over the course of a speech.
4. Terminal credibility is acquired after the speech.
5. Having high credibility gives the speaker an advantage.
Student Resource
Gamble, The Public Speaking Playbook, 2nd Edition
SAGE Publishing, 2018
III. Use evidence or logos arguments convince an audience by using logic.
A. Logos involves uniting credibility with evidence and reasoning.
1. Back your positions with strong evidence.
B. A fact is a statement that direct observation can provide true or false.
1. An inference is a conclusion based on facts.
a. Persuasive speakers have to draw conclusions on
inferences.
2. To confirm the validity of a fact or inference that are incorporated into a
persuasive argument, speakers should investigate if there is any
controversy regarding whether the statement is made true.
3. Speakers should also investigate if the statement is made by someone
who was a first witness of the situation or event.
C. Statistics are numbers that summarize a group of observations.
1. Statistics should be used if they meet the following criteria:
a. The statistics are recent.
b. The statistics are from an unbiased source.
c. The statistics are uncontroversial.
d. The statistics are representative of the entire population.
D. Examples and illustrations are used to develop facts.
1. Speakers may use specific instance or brief examples.
2. Illustrations are narratives that add more drama and emotional
involvement to a message.
3. Examples and illustrations should be used if they meet the following
criteria:
a. The example or illustration is typical or representative of what
occurs.
b. The example or illustration is significant or clearly influence a
number of things.
c. The example or illustration is not surrounded by controversy.
d. The example or illustration comes from a reliable source, one
that is considered as an authority by the audience.
E. Testimony consists of the opinions of respected individuals to add to the
credibility to the conclusions that are drawn within the speech.
1. Testimonials should be used if the source is a recognized expert and has
no stake in the issue.
Student Resource
Gamble, The Public Speaking Playbook, 2nd Edition
SAGE Publishing, 2018
2. Testimonials should be consistent with the statements of other experts
and are not contrary to what the source has said in the past.
IV. An inference is a conclusion we draw based on fact.
A. They connect the dots for your audience, demonstrating how the facts you’ve
presented support your position.
1. Assess the validity of your inferences
2. Must have high probability of truth
3. To confirm the validity, apply two criteria:
1. There is little, if any, controversy regarding whether the statement made
is true or
2. The statement made is based on a report by someone who directly
observed the situation or event.
V. Logos arguments appeal to reason.
A. Toulmin argued that effective reasoning consisted of the following:
1. Claim or debatable conclusion or assertion, the proposition or thesis.
2. Data or good reasons, facts and evidence for making the claim.
3. A warrant or logical and persuasive relationship that explains you to
get the claim on the basis of the data.
4. The backing, consists of supporting information that strengthens the
warrant when the warrant is controversial.
5. The qualifier places limitations on the connection between the data and
warrant.
6. The rebuttal consists of potential counterarguments.
B. Based on the Toulmin Reasonable Argument Model, there are four methods
of reasoning that speakers can use to encourage an audience to support the
advocated position
1. Deductive reasoning is used when a speaker moves from the general to
the specific.
2. Deductive reasons take the form of syllogisms or the patterns that
structure an argument. A syllogism has three parts:
a. Major premise is the general statement or truth
b. Minor premise is a more specific statement that describes a
claim made about a particular object
c. The conclusion emerges from the major and minor premise.
3. Major and minor premises must be true and the conclusion must follow
logically from the premise.
4. Speakers are encouraged to present the major premise first.
Student Resource
Gamble, The Public Speaking Playbook, 2nd Edition
SAGE Publishing, 2018
C. Inductive reasoning begins with specific observations and then moves to a
more general claim or conclusion.
1. When using inductive reasoning a speaker must determine if there are
enough reasons given to justify a conclusion and if the instances that are
cited are typical and representative.
D. Causal reasoning unites two or more events to illustrate that one or more of
them caused the other.
1. When using causal reasoning a speaker should determine if the caused
that is cited is real or actual and if the cause is an oversimplification.
E. Reasoning from analogy occur when comparing like things and concluding
that because they are comparable in a number of ways they are also comparable in
other ways.
1. When reasoning from analogy a speaker must determine if the objects
of the comparison are alike in essential aspects (are they more alike than
they are different).
2. Speakers must determine if the differences between the objects are
significant.
VI. Pathos arguments convince an audience with emotion.
A. Aristotle argued that speakers should use emotion to instill the audience with
attitudes and beliefs similar to their own to elicit a desired response.
B. Maslow’s Hierarchy of Needs explains human motivation.
1. The basic human need is survival.
2. The next basic human need is safety.
3. The next basic human need is to belong and to feel loved.
4. The fourth basic need is to feel good about ourselves and to know that
others respect and value us.
5. The last basic need is self-actualization or the need to realize our fullest
potential and to accomplish those things.
6. If speakers can identify the needs of the audience, they can obtain the
audience’s attention and control the level of audience involvement and
receptiveness.
C. For an pathos based appeal to work, an audience must believe
1. The speaker is credible.
2. The threat that is described is real.
3. The proposed to solution with will a state of balance.
VII. Speakers must use the three tenets of persuasion
A. Speakers should not skip too many steps at one time or expect too much from
the audience at the end of the speech.
Student Resource
Gamble, The Public Speaking Playbook, 2nd Edition
SAGE Publishing, 2018
1. Speakers should demonstrate how the current situation has created an
inconsistency in their lives and how you can help them restore balance.
2. Speakers should place the strongest argument first to win the audience
early in the presentation or place the strongest argument at the end to build
momentum for change and acceptance.
a. The middle of the speech is the weakest position. Placing the
strongest argument in the middle of the discussion works against
the overall success of the argument.
VIII. Speakers have an ethical responsibility to avoid using weak or flawed arguments.
A. A logical fallacy is a flawed reason and It is unethical to propose logical
fallacies to an audience.
1. Hasty generalization is one type of flawed argument or logical fallacy.
a. This occurs when a speaker is too quick to draw an inference
and jump to a conclusion based on too little evidence.
2. Post hoc ergo propter hoc is a type of logical fallacy that occurs when a
speaker assumes that because one event preceded another, the first event
caused the second to happen.
a. Correlation is not causation.
3. A slippery slope is a type of non-sequiter that occurs when one action
will set in motion a chain of events.
4. A red herring is another type of logical fallacy that occurs when a
speaker leads the audience to consider an irrelevant issue instead of the
topic at hand.
5. A false dichotomy is another type of logical fallacy that occurs when
the audience is given only two options that appear to be polar opposites
when in reality there are other options.
6. A false-division occurs when the speaker infers that if something is true
of the whole it is also true of one or more of the parts.
7. Personal attacks occur when a speaker gives an idea, person, group, or
political position a bad name so that others will condemn the target without
critically examining the evidence.
8. A glittering generality occurs when a speaker convinces an audience to
accept an idea by associating the idea with things that the audience would
value highly without examining the evidence.
9. Ad hominem attacks occur when asking your audience to reject an
idea because of the flaw in a person associated with that idea.
10. The bandwagon appeal is used to encourage an audience to do
something because everyone else is doing the same.
11. Fear appeal serve as another type of logical fallacy
Student Resource
Gamble, The Public Speaking Playbook, 2nd Edition
SAGE Publishing, 2018
a. Speakers who make audiences feel overly fearful to
accomplish his or her goals.
b. Speakers pander to prejudices and escalate the legitimate
fears of the audience.
12. Appeals to tradition are another type of logical fallacy
a. When appealing to tradition the audience is asked to accept
an idea because that’s the way it has always been done..
13. Appeals to misplaced authority function as another type of logical
fallacy.
a. This fallacy relies upon a lack of critical thought by using a
well-liked personality who endorses an idea but knows little
to nothing about it.
14. The straw man occurs when a speaker asks the audience to ignore
another position by using an inequivalent, distorted, or exaggerated for it.