The Logical Structure of ArgumentsBy: Justin Frank Heather GregoryMatt Howard

AssumptionsWomen should be allowed to join combat units because the image of women in combat would help eliminate gender stereotypes.

Enthymeme The Greek philosopher Aristotle showed how

successful enthymemes root the speaker’s argument in assumptions, beliefs, or values held by the audience.

The word enthymeme comes from the Greek en (meaning “in”) and thumos (meaning “mind”).

Readers must have “in mind” an assumption, belief, or value that lets them willingly supply the missing premise or the argument fails.

Because Clause Claims are supported with reasons. You can

usually state a reason as a because clause attached to a claim.

A because clause attached to a claim is incomplete logical structure called an enthymeme. To create a complete logical structure from an enthymeme, the underlying assumption (or assumptions) must be articulated.

To serve as an effective starting point for the argument, this underlying assumption should be a belief, value, or principle that the audience grants.

Identifying Underlying Assumptions CLAIM Women should be allowed to join

combat units REASON because the image of women

in combat would help eliminate gender stereotypes.

UNDERLYING ASSUMPTIONGender stereotypes are harmful and should be eliminated.

Stephen Toulmin Toulmin’s courtroom model differs from formal

logic in that it assumes that…(1)All assertions and assumptions are contestable by “opposing counsel” and that(2)All final “verdicts” about the persuasiveness of the opposing arguments will be rendered by a neutral third party, a judge or a jury.The judge and jury reminds us to answer opposing arguments fully and to present positive reasons for supporting our case as well as negative reasons for disbelieving the opposing case.

Warrant Warrant- the underlying assumption that

turns an enthymeme into a complete logical structure.

The warrant is a value, belief, or principle that the audience has to hold if the soundness of the argument is to be guaranteed or warranted.

Grounding and Backing Grounds and backing are facts,

statistics, and examples that support and back your reason and make for a more convincing argument.

(the blood and muscle that flesh out the skeletal frame of your enthymeme.)

Toulmin suggests that grounds are “what you have to go on.”

Rebuttal Toulmin’s system asks us to imagine

how a resistant audience would try to refute out argument. Sort of like a defense team.

Reason for rebuttal are to look at the perspective of skeptics.

Qualifier Indicates a degree of its probable truth. If there are exceptions to your warrant

or if your grounds are not very strong, you will have to qualify your claim. (Claim and reason)

ENTHYMEMECLAIM Cocaine and heroin should be legalizedREASON because legalization would eliminate the black market in drugs.

GROUNDSStatistical evidence and arguments showing how legalization would end black market: Statistics and data showing

the size of the current black market

Examples, anecdotes, facts showing how the black market works

WARRANTEliminating the black market in drugs is goodBACKINGStatistics and examples about the ill effects of the black market The high cost of the

black market to crime victims

The high cost to taxpayer of waging the war against drugs

CONDITIONS OF REBUTTAL

Attacking the reason and grounds

Arguments showing that legalizing cocaine and heroin would not eliminate the black market in drugs

Perhaps taxes on the drugs would keep the costs above black market prices

Perhaps new kinds of illegal designer drugs would be developed and sold on the black marker

Attacking the warrant and backing

Arguments showing that the benefits of eliminating the black market are outweighed by the costs The number of new drug

users and addicts would be unacceptably high

The health and economic cost of treating addiction would be too high