The Rhetorical Triangle:
Understanding and Using Logos,
Ethos, and Pathos
Environmental Science and Technology
HS
Background
• Aristotle taught that a
speaker’s ability to persuade
an audience is based on how
well the speaker appeals to
that audience in three
different areas: logos, ethos,
and pathos. Considered
together, these appeals form
what later rhetoricians have
called the rhetorical triangle.
Balance and Purpose
 The rhetorical triangle is
typically represented by an
equilateral triangle,
suggesting that logos,
ethos, and pathos should
be balanced within a text.
 However, which aspect(s) of
the rhetorical triangle you
favor in your writing
depends on both the
audience and the purpose
of that writing. Yet, if you
are in doubt, seek a balance
among all three elements.
Definitions
• Logos appeals to reason. Logos can also be thought of
as the text of the argument, as well as how well a writer
has argued his/her point.
• Ethos appeals to the writer’s character. Ethos can also
be thought of as the role of the writer in the argument,
and how credible his/her argument is.
• Pathos appeals to the emotions and the sympathetic
imagination, as well as to beliefs and values. Pathos can
also be thought of as the role of the audience in the
argument.
Logos: Appeals to Reason or Logic
DOs:
 Evidence
 Reasons
 Opinions
 Examples
 Facts
 Data
 Grounds
 Proof
 Premise
 Statistics
 Explanations
 Information
DON’Ts (Fallacies):
• Begging the question
• Red herring
• Straw man
• Post hoc
• Hasty generalization
Premise and Conclusion
• Premises are statements of (assumed) fact which are
supposed to set forth the reasons and/or evidence
for believing a claim.
• The claim, in turn, is the conclusion
• 1. Doctors earn a lot of money. (premise)
2. I want to earn a lot of money. (premise)
3. I should become a doctor. (conclusion)
Ethos: Credibility of the Writer
DOs:
 Be knowledgeable about your
issue by
- Examples
- Personal experience
- Statistics
- Empirical data
 Be fair
- Demonstrate fairness and
courtesy
- Empathize with other points of
view
 Build a bridge to your Audience
- Ground your argument in shares
values (See warrants, assumptions,
widely held values, general
principles, etc.)
DON’Ts (Fallacies):
•
Ad hominem
•
Authority instead of evidence
Pathos: Appeals to Emotion
DOs:
DON’Ts (Fallacies):
• Use concrete language
• Use specific examples
and illustrations
• Provide evidence
• Give presence and
emotional resonance
• Use narratives
• Use images, comparisons
and analogies
• Bandwagon appeal
• Slippery slope
Guiding Questions
 The following questions can be used in two ways,
both to think about how you are using logos,
ethos, and pathos in your writing, and also to
assess how other writers use them in their writing.
Logos:
 Is the thesis clear and specific?
 Is the thesis supported by strong reasons and
credible evidence?
 Is the argument logical and arranged in a wellreasoned order?
Guiding Questions
Ethos:
• What are the writer’s qualifications? How has the writer connected
him/herself to the topic being discussed?
• Does the writer demonstrate respect for multiple viewpoints by
using sources in the text?
• Are sources credible? Are sources documented appropriately?
• Does the writer use a tone that is suitable for the audience/purpose?
Is the diction (word choice) used appropriate for the
audience/purpose?
• Is the document presented in a polished and professional manner?
Guiding Questions
Ethos:
• What are the writer’s qualifications? How has the writer connected
him/herself to the topic being discussed?
• Does the writer demonstrate respect for multiple viewpoints by
using sources in the text?
• Are sources credible? Are sources documented appropriately?
• Does the writer use a tone that is suitable for the audience/purpose?
Is the diction (word choice) used appropriate for the
audience/purpose?
• Is the document presented in a polished and professional manner?
Final Thoughts
• While the previous information presents logos, ethos, and
pathos in as separate elements in writing, it is important to
remember that sometimes a particular aspect of a text will
represent more than one of these appeals.
• For example, using credible sources could be considered both
logos and ethos, as the sources help support the logic or
reasoning of the text, and they also help portray the writer as
thoughtful and engaged with the topic. This overlap reminds
us how these appeals work together to create effective
argumentative writing.
Fallacies in Argument
A fallacy is a common error in
reasoning which people often fail to
notice in their own arguments or which
others may use in their arguments in the
hope that we won't notice them.
Fallacies in Argument
A fallacy is a common error in
reasoning which people often fail to
notice in their own arguments or which
others may use in their arguments in the
hope that we won't notice them.
Begging the Question
• An argument that begs the question asks the reader
to simply accept the conclusion without providing
real evidence; the argument either relies on a
premise that says the same thing as the conclusion
(which you might hear referred to as "being
circular" or "circular reasoning"), or simply ignores
an important (but questionable) assumption that the
argument rests on.
Red Herring
• Partway through an argument, the arguer goes off
on a tangent, raising a side issue that distracts the
audience from what's really at stake. Often, the
arguer never returns to the original issue.
Straw Man
• One way of making our own arguments stronger is
to anticipate and respond in advance to the
arguments that an opponent might make.
• In the straw man fallacy, the arguer sets up a weak
version of the opponent's position and tries to score
points by knocking it down.
• However, just as being able to knock down a straw
man (like a scarecrow) isn't very impressive,
defeating a watered-down version of your
opponent's argument isn't very impressive either.
Post Hoc (False Cause)
• Assuming that because B comes after A, A caused B.
Of course, sometimes one event really does cause
another one that comes later—for example, if I
register for a class, and my name later appears on
the roll, it's true that the first event caused the one
that came later.
• However, sometimes two events that seem related in
time aren't really related as cause and event.
• That is, correlation isn't the same thing as causation.
Hasty Generalization
• Making assumptions about a whole group or range
of cases based on a sample that is inadequate ,
atypical , or too small.
Fallacies
ETHOS
Ad Hominem
• The arguer focuses our attention on people rather
than on arguments or evidence.
• The arguer attacks his or her opponent instead of
the opponent's argument.
Appeal to Authority
• Often we add strength to our arguments by
referring to respected sources or authorities and
explaining their positions on the issues we're
discussing.
• If, however, we try to get readers to agree with us
simply by impressing them with a famous name or
by appealing to a supposed authority who really isn't
much of an expert, we commit the fallacy of appeal
to authority.
Fallacies
PATHOS
Fallacies
PATHOS
Slippery Slope
• The arguer claims that a sort of chain reaction,
usually ending in some dire consequence, will take
place, but there's really not enough evidence for that
assumption.
• The arguer asserts that if we take even one step onto
the "slippery slope," we will end up sliding all the
way to the bottom; he or she assumes we can't stop
partway down the hill.
Critique: Fallacies in Argument
For each of the 9 arguments:
On the handout:
1. Identify the premise and conclusion. LABEL each of these on the
handout.
2. Identify what the arguer was attempting to appeal to (logos, ethos,
pathos). LABEL each argument on the handout.
3. Identify the fallacy that the writer committed on the handout. LABEL
each argument on the handout.
On a piece of lined paper (1 paper for you and your partner)
1. Write a paragraph that provides a rationale for your choice on a lined
piece of paper
– Topic Sentence: State the fallacy
– Evidence: Refer to specific points of the argument to prove why the
argument is the fallacy that you selected.
– Link: Explain why the arguer is guilty of the fallacy.
– Concluding Sentence: Synthesis
Example #8- Begging the
Question
"Active euthanasia is morally acceptable. It is a
decent, ethical thing to help another human
being escape suffering through death."
• Logos
• Premise: It is a decent, ethical thing to help
another human being escape suffering through
death.
• Conclusion: Active euthanasia is morally
acceptable
Rationale- Begging the Question
Topic Sentence: The arguer hasn't yet given us any real reasons why
euthanasia is acceptable; instead, her argument "begs" (that is, evades) the
real question.
Evidence and Link: If we "translate" the premise, we'll see that the arguer
has really just said the same thing twice: "decent, ethical" means pretty
much the same thing as "morally acceptable," and "help another human
being escape suffering through death" means something pretty similar to
"active euthanasia.” The premise basically says, "active euthanasia is morally
acceptable," just like the conclusion does.
Concluding Sentence: The arguer has not provided the audience with any
reasons, evidence, and is redundant. The audience is left with no answers.