1:45-3:15 Panel 2
Annenberg Forum, Carswell Hall
Chair: Bart Garssen, University of Amsterdam
David Godden, Old Dominion University, ‘Corroborative Evidence’
László I. Komlósi, University of Pécs, Hungary, ‘Presumptive Argumentation Giving Rise to Meta-Argumentative Maneuvering Supervening Normative Pragmatics’
Frank Zenker, Lund University, Sweden, ‘Deduction, Induction, Conduction: An Attempt at Unifying Natural Language Argument Structure’
1st speaker: Godden, David M., Old Dominion University
Corroborative Evidence
Corroborative evidence can have a dual function in argument. First it can provide direct evidence supporting the main conclusion, and second it can bolster the value of some other piece of evidence. This dual character can over value a piece of evidence and lead to the fallacy of double counting.
Convergent Corroborative Arguments: First a corroborating reason strengthens the main conclusion by providing an independent reason for the main conclusion, second it also increases the strength of at least one other reason in the argument.
Walton (2008) defines Premise Support as corroborating argument supports one premise of the original argumentand clarifies that in a Corroboration Scheme each piece of evidence should have its own argumentation scheme.
Convergent corroborative evidence gives direct support while supportive corroborative evidence supports the inferential link between corroborated evidence and the primary conclusion.
Redmayne (200) argues that the fallacy of double counting over-values and therefore a subtraction must occur.
Godden argues that the bolstering effect is legitimate, and can be explained by recourse to inference to the best explanation.
His example from Elgin (2005) in rebuttal involves a group of independent but individually unreliable witnesses all give substantially the same account of an event. While we should discount any one an explanation of the concurrence of all must be found.
2nd speaker: Laszlo I. Komlosi, University of Pecs, Hungary
Presumptive Argumentation Giving Rise to Meta-Argumentative Maneuvering Supervening Normative Pragmatics
Dual challenge to the traditional idea of presumptive reasoning (PR) based upon the burden of proof: first, PR is a paradigm in assessing the expectations of others, however, second PR schemes can simultaneously destabilize certainties…leading to meta-argumentative rules of maneuvering.
Offers the removal of the English national soccer team captain. Three moral claims:
- Claim 1: The man who lacks morals cannnot lead the team.
- Claim 2: The man who has committed adultery should not be soccer team captain.
- Claim 3: The man whose adultery has become publicly known should not be captain.
As the case aged other information complicated the story; Terry tried to block the story with an injunction against the tabloid that published the account. Is this a cultural response against Terry?
Komolosi then provides a long list of of headlines from the press.
The presentation then shifts to an example of political campaign promises that are not kept. This discrepancy often does not prove detrimental to the party.
Komolosi offers three presumptions in a dialogue between a current prime minister (CPM) and a former prime minister (FPM), within the context of a pre-electoral debate:
- CPM asserts: citizens compare achievements to the previous government
- FMP asserts: people vote by looking at their current difficulties and weighing future prospects
- CPM asserts: the discrepancy regarding politician’s promises and actions after election is simply a fact of life.
Each side has a tacit agreement not to advertise the above assumptions.
A dialogue shift might occur if the CPM initiates a presumption that the speeches of politicians consist in keeping promising to the people.
3rd speaker:Zenker, Frank, Lund University, Sweden
Deduction, Induction, Conduction: An Attempt at Unifying Natural Language Argument Structure
Are the three Deduction, Induction, Conduction distinct?
For Conductive Structure the Abstract properties of natural arguments (not their contents), reconstructable such that:
- Pro-reasons and counter-considerations …partially ordered on some scale introduce notion of comparative importance
- Pro-reasons confer positive and con-reasons negative support to the conclusion or some group element
- On balance principle
Zenker’s Criteria for distinguishing Deduction, Induction, Conduction type structures
1) Comparative difference between informational content of premise-set vis s vis conclusion
2) Dynamic behavior of support relation between premises and conclusion under p-revision.
Where
- support relation = argumentative strength of justificatory force;
- dynamic behavior = effect suffered by this support relation upon premise retraction or addition;
- premises & conclusion = natural language sentences & their (descriptive or normative) contents.
he then details with formula the three types types
- deductive
- inductive
- conductive
He then provides example of each and then proposes a Two Step “Reduction”
Step 1: Generate inductive structure from conductive one: Range of assignable weights constrained from R+ to constant value
Step 2: Generate the deductive structure from the inductive one: informational content of the conclusion reduced by a supplied formula
He then suggests three evaluative criteria (weight difference, non zero weight assignment, differentiability).