Glossary & Key Concepts

What is an Argument?

  • Argument: Communication in which the speaker is trying to persuade their audience to believe, feel or do something by giving reasons.
    • vs. Fight: In a fight, the speaker is just trying to get their way, regardless of whether or not they change their audience’s mind or persuade them to agree. 
    • vs. Description: In a description, the speaker explains what happened, gives information, or tells a story. Their goal is to inform or entertain the audience, rather than convince the audience of a main point. 
  • Why We Argue: 
    • Truth 
    • Justice
    • Connection
    • Skills
  • How We Argue: The dispositions of strong critical thinkers
    • Humility (“I could be wrong”)
    • Openness (“You could be right”) 
    • Value having good reasons for your beliefs
    • The Charity Principle: Treat other people’s arguments how you want them to treat yours

Argument Components

  • Claim: A statement that someone wants you to believe.
    • Main Claim: The main point of the argument; the primary thing the speaker wants the audience to believe.
    • Premise: A claim that gives a reason to believe another claim. 
      • Evidence: Concrete, specific factual information presented to support a claim, e.g. quote from a text, historical source, piece of data
      • Reasoning: Explains how/why the evidence helps to prove the claim. 
    • Objection: A claim that gives a reason not to believe another claim. 
    • Rebuttal: A response to an objection. 

Indicator Words

Main ClaimPremiseObjection
ThusSeeing asYet
HenceGiven thatEven though
ErgoConsider thatAlthough
AccordinglyIn light ofCritics say
As suchFirst/second/third, additionally, furthermore, also, moreover, besides, etc.On the other hand

The Reason Rule

In an argument map, every single premise must always answer the question “why believe this?” about the claim above it. (You should only include a statement in your map if it gives a reason to believe the statement above it.)

Argument Structure Types

Independent Premises: give you separate, distinct reasons to believe the claim above. 

Sub-Premise: a premise that gives you a reason to believe another premise. Arguments with at least one sub-premise are called chain arguments.

Co-Premises: work together or “hold hands” to give one single reason to believe the claim above. (Think of two people making a chair with their hands to carry someone else.)

  • Each co-premise logically connects the other co-premise to the claim above. It spells out how the other co-premise is relevant to the claim above. 
  • If one co-premise is false, the other co-premise does not work as a reason to believe the claim. (Whereas independent premises still work as a reason, even if the other premise is false). 
  • Hidden co-premise: A co-premise that the author assumes but does not explicitly state in their argument. (Often, the true source of a disagreement lies in hidden assumptions.)
  • One common form of co-premises is Evidence+Reasoning (see definitions above).

Evaluating Arguments

Two-step test:
1. Are the premises true or false? (How plausible/ reasonable are they?) 
2. Are the inferences strong or weak?

1. Premises/ Evidence ( = building materials) 2. Inferences ( = structural design)
GoodTrue (probable, reasonable)Strong (relevant, sufficient)
BadFalse (improbable, unreasonable)Weak (irrelevant, insufficient)
  • Are the premises relevant to why you should believe the main claim? 
  • Do the premises give you a sufficient reason to believe the main claim?
  • Remember, an argument can have true premises with weak inferences (solid materials, bad design), or false premises with strong inferences (lousy materials, good design) or both/neither. 

What makes an argument good?

  • State a clear main claim
  • Use true premises
    • Given a choice, try to appeal to the audience
  • For empirical (descriptive) claims:
    • Give examples to clarify and illustrate
    • Cite evidence from reliable sources
  • Explain the relevance of the premises to supporting the main claim
    • Be explicit about key assumptions
  • Use precise, specific, and moderate language
  • (Generally) Offer multiple independent lines of reasoning
  • (Generally) Consider and respond to at least one objection