Rhetoric, Logic, Argumentation, Fallacies

1. Rhetoric, Logic, and
Argumentation

2. What is Rhetoric?
-the art that humans use to process all the messages we send and receive
Rhetorical Choices
• -what a writer uses to get the meaning across
We focus on two things
I. Analyzing all the language choices that are used to establish the text's
meaning,
purpose, and effectiveness
II. Examining the features of the text that establish rhetoric.

3. How to be skilled at Rhetoric
a. excellent writing skills
b. read critically
c. able to examine a situation and
determine what has already been said ,
what remains unresolved,
and what you can say to continue the
conversation or persuade readers to take
action.

4. The Rhetorical
Triangle
The 3 rhetorical
appeals

5. Appeal to Ethos: moral character
• In an appeal to ethos the speaker (rhetor)
emphasizes the strength of their own moral
character and experience in order to establish
personal credibility.

6. The Rhetor
• The rhetor creates a persona-a mask-the character that the
audience perceives behind the text
• is based in part on who the rhetor presumes the audience to be
and in part on what he or she
• knows and believes about the subject of the text: what evidence
or proof are the most
• compelling and persuasive?
•
Members of the audience, hold some beliefs, based on their
background knowledge and experiences,
• about the rhetor and the subject and they tap into these beliefs
as they listen. Also, the audience,
• uses their ability to reason-and they are persuaded by the
strength of the evidence presented.

7. Appeal to Pathos: emotion
• An appeal to pathos attempts to elicit an
emotional response from the audience.

8. Appeal to Logos: reason, logic,
words.
• An appeal to logos relies on the use of rational
analysis and persuasive language.

9. QUIZ: logos, pathos, rhetoric, audience, ethos, message, speaker
• 1. Related to the audience’s feelings
• 2. “The art of ruling the minds of men.”
• 3. Emphaiszes reason and proof.
• 4. The individual (s) on the receiving end of the communication.
• 5. The individual presenting the argument in speech, writing, or another medium.
• 6. The ideas being communicated.
• 7. Emphasizes the speaker’s/rhetor’s character

10. Cognitive Bias
• Express a hardwired preference for certain
flawed patterns
• Because you think means you already have bias
▫ -your audience is already biased
• Don’t believe everything you think
▫ Generally see the world as better
▫ See others as worse
▫ See patterns where there are none
▫ Wired to block out people who oppose us

11. Gambler’s Fallacy, Confirmation Bias, Illusory Superiority, bandwagon Effect, Halo
Effect, Wishful Thinking, Framing Bias, Clustering Illusion, Self-Serving Bias
• 1. I’ve found at least 30 articles that confirm my idea that some people have
extrasensory perception. I’ve also seen reports that disagree, but I have not read any
of them.
• 2. I don’t think anyone actually has ESP; everyone I know says that the whole consent
is a myth.
• 3. I think some people do have psychic abilities; I would love to think that it’s possible
to predict the future.
• 4. Some people can foresee the future, but I don’t think that people can have psychic
abilities.
• 5. I’ve notices that every time I think about my best friend, Jessica, she calls me.
That’s why I think Jessica has ESP.
• 6. When I called the psychic

12. Deductive vs Inductive Arguments
• Deductive
▫ 1. propose a set of principles
▫ 2. form a conclusion by making a logical inference
from these principles
▫ 3. the conclusion is a logical consequence of the
premises
▫ 1. All teachers assign homework.
▫ 2. Mrs. Martin is a teacher.
▫ 3. Therefore, Mrs. Martin assigns homework.

13. Syllogism-a deductive argument composed of two premises (major
and minor) and a conclusion
• Major Premise: 1. All men are mortal.
• Minor Premise: 2. Socrates is a man.
• Conclusion: 3. Therefore, Socrates is a mortal.

14. • Inductive-do not prove that a certain conclusion
must be true. They prove that the conclusion is
PROBABLY true.
• 1. All the students I know hate homework.
• 2. Cynthia is a student.
• 3. Therefore, Cynthia probably hates homework.

15. Deductive Inductive
• 1. All feathered animals are
birds.
• 2. Chicken Little has feathers.
• 3. Therefore, Chicken Little is
a bird.
• Chicken Little is a bird.
• Most birds eat insects.
• Therefore, Chicken Little
probably eats insects.

16. Valid-structure is correct
Sound-the statements must be
true and the structure must be
correct
• 1. All bananas are purple.
• 2. Socrates is a banana.
• 3. Therefore, Socrates is
purple.
• 1. There are 12 inches in a foot.
• 2. There are 3 feet in a yard.
• 3. Therefore, there are 36
inches in a yard.

17. Logical Fallacies
• Fallacy means error
• Logical fallacy is a mistake in reasoning

18. Non Sequitur
• It does not follow
• 1. All aardvarks are mammals.
• 2. All mammals are animals.
• 3. Therefore, all animals are aardvarks.

19. Non Causa Pro Causa “non cause for cause”
• The fallacy of mistaken causation.
• These arguments mistake mere coincidence or
correlation for causation.
• My grandmother lived to the age of 98.
• My grandmother ate chocolate every day.
• My grandmother lived to the age of 98 because
she ate chocolate every day.

20. Cum Hoc, Ergo Propter hoc “With this,
therefore because of this”
• The speaker assumes there is a causal
relationship between two factors simply because
they occur at the same time
• Scientists confirm link between ADD and cell
phones
▫ Studies have shown that since the use of cell phones has become
more widespread worldwide, diagnoses of ADD have increases
dramatically. These findings seem to suggest that the radiation
emitted by cell phones may cause ADD in some users.

21. Post Hoc, Ergo Propter Hoc “after this,
therefore because of this”
• The speaker attempts to argue that one thing has
caused another using only the chronological
sequence of evens as evidence .
• The event that happens first is assumed to have
caused the events that follows.
▫ The Society for a Bread-Free Nation claims that
more than 90 percent of violent crimes are
committed within 24 hours after the perpetrator
has eaten bread. These findings seem to suggest
that consuming bread inspires violent behavior.

22. Hasty Generalizations
• The speaker makes a weak analogy between the
part and the whole, but the part does not truly
exemplify the whole.
• Chester is a cat.
• Chester has no tail.
• Therefore, cats have no tails.

23. Stereo-Types
• They are all the same to me!
• Is a widely accepted, simplistic view of a people
who belong to a given group.
• All politicians I have known lie.
• All politicians are exactly like the politicians I
know.
• Therefore, all politicians are liars.

24. Loaded Questions
• It is a fallacy of interrogation
• This type of fallacy occurs in the form of a
question
• They are loaded with assumptions.
• When was the last time you did drugs?
• Have you stopped beating your wife?
• Why do gun owners like violence?

25. Red Herring
• Arguments that divert attention from the true
issues of a debate by emphasizing irrelevant
information.

26. Argument from Authority
• Four out of five experts recommend it.
• The US Surgeon General uses a PC.
• Therefore, PCs are better than Macs.

27. Ad Hominem
• Meant to divert attention from the legitimate issues of the debate.
• Argument “against the man”
• The speaker suggests that an opponent's argument should be
rejected on the basis of some quality of the speaker that is not
logically related to the credibility of his or her argument.
• A. my research demonstrates that using pesticides in the home
increases the risk of cancer.
• B. Have you had cancer?
• A. No.
• B. Then you’re in no position to know whether pesticides cause
cancer.

28. Guilt by Association
• The speaker attempts to malign an opponent by
associating him or her with a negative concept.
• The fallacy is based on the false notion that if an
individual can be linked in any way to something
offensive, it is fair to equate

29. Straw Man
• These arguments are a diversionary tactic
• The speaker avoids addressing an opponent’s argument directly by creating and
attacking a “dummy” argument that does not accurately represent the opponent’s
stance.
• Whenever a speaker describes an opponent’s argument in a dishonest way, instead
choosing to represent a distorted, extremist, or simply absurd version of the
argument.
• The Senator from Vermont has suggested that we dismantle our North Atlantic Radar
System, now that the Soviet union is no long a threat. I don’t understand why he
would want the United States to be defenseless.

30. Emotional Appeal
• Speaker attempts to persuade an audience
through emotional manipulation.
• You should eat everything on your plate because
there are starving children in Africa.
• If you don’t donate your kidney, you are
murdering someone.