The Logical Structure of Arguments

1. The Logical Structure of Arguments By: Justin Frank Heather Gregory Matt Howard

2. Assumptions • Women should be allowed to join combat units because the image of women in combat would help eliminate gender stereotypes.

3. 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.

4. 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.

5. 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 ASSUMPTION Gender stereotypes are harmful and should be eliminated.

6. 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.

7. 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.

8. 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.”

9. 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.

10. 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)

11. ENTHYMEME CLAIM Cocaine and heroin should be legalized REASON because legalization would eliminate the black market in drugs. WARRANT Eliminating the black market in drugs is good BACKING Statistics 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 GROUNDS Statistical 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

12. CONDITIONS OF REBUTTAL Attacking the reason and grounds 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 • 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