Argumentation and Rhetoric: Claims, Evidence, Models, and Fallacies

Argument

A process of reasoned inquiry and rational discourse seeking common ground.

Claim

An assertion that states the argument's main idea or position.

Claims of fact

Assert that something is true or not true.

Claims of value

Argue that something is good or bad.

Claims of policy

Propose a change.

Evidence

Support for a claim or argument.

Personal experience

Evidence drawn from the writer's own experience.

Personal observations

Evidence that the writer has seen but not necessarily experienced.

Testimony

Expression of how a writer or someone the writer is citing feels about a personal experience or observation.

Anecdotes

Stories about other people that you've observed, been told about, or researched.

Analogies

Comparisons between two unlike things.

Current events

What is happening globally or locally.

Historical information

Verifiable facts that a writer knows from research.

Expert opinion

The backbone of evidence-based argument because it draws on specialized credible knowledge.

Quantitative evidence

Evidence that can be represented in numbers and may be presented in explanations.

Lines of reasoning

The connections between the claims in the writer's argument and the evidence.

Thesis

Overarching claim that clearly states the writer's position.

Induction

Arranging an argument so that it leads from particulars to universals, using specific cases to draw a conclusion.

Deduction

Moving from a general statement to a specific conclusion.

Syllogism

Logical structure that uses a major premise and minor premise to reach a logical conclusion.

Classical argument

Five-part structure for an oratory or speech.

Introduction (exordium)

Introduces the reader to the subject under discussion.

Narration (narratio)

Provides factual information and background material on the subject at hand.

Exposition

Establishes why the subject is a problem that needs addressing.

Confirmation

Contains the most specific and concrete detail in the text.

Refutation

Addresses the counterargument and serves as the bridge between the writer's proof and conclusion.

Conclusion (peroratio)

Brings the essay to a close.

Rogerian arguments

Based on the assumption that fully understanding an opposing position is essential to responding to it.

Toulmin model

A tool for uncovering the assumptions that underlie arguments.

Warrant

Expresses the assumption necessarily shared by the speaker and audience.

Assumption

Corresponds directly to the warrant.

Backing

Further assurances or data without which the assumption lacks authority.

Qualifier

Tempers the claim, making it less absolute.

Reservation

Explains the terms and conditions necessitated by the qualifier.

Rebuttal

Gives voice to objections.

Method of development

Narration, cause and effect, comparison and contrast, definition, and description.

Narration

Telling a story or recounting a series of real-life events.

Cause and effect

Analyzes the causes that lead to a certain effect or the effects that result from a cause.

Comparison and contrast

Juxtaposes two things to highlight their similarities and differences.

Definition

A mode of expression that requires careful distinction.

Description

Closely allied with narration because both include specific details and evoke the senses by painting a picture.

Logical fallacies

Vulnerabilities in an argument caused by faulty reasoning or incorrect use of evidence.

Red herring

Occurs when a speaker shifts to a new and irrelevant topic to avoid the topic of discussion.

Ad hominem fallacy

A diversionary tactic that switches the argument from the issue at hand to the character of the other speaker.

Straw man fallacy

When a speaker chooses a deliberately poor or oversimplified version of an opponent's viewpoint to ridicule or refute it.

Either-or fallacy / false dilemma

Presents two extreme options as the only possible choices.

Post hoc ergo propter hoc

Incorrectly claiming that something caused an event just because it happened earlier.

Faulty analogy

Focuses on irrelevant or unimportant similarities between two things.

Hasty generalization

A faulty conclusion reached from a lack of adequate evidence.