After spending September 11, 2008 at Ground Zero and engaging various members of the public on subject of 9/11, I thought to share a few common points of informal debate that frequently ensued on the street.
It is interesting to note that logical hazards can occur on either side of deliberation and that a refined understanding of an issue is traditionally considered to be the prime objective.
Those more educated in polemics, please feel free to correct and inform the thread. Please also note that I’ve marked arguments as [counter and (mutual per 9/11 skepticism.
Finally, although I believe our discussions are of civic and intellectual value, it would seem that that the most effective method of understanding the events of 9/11 is through a trial subject to due process in court.
Cheers,
MG

DEBATE

Definition: formal method of suppositional argument, including rules and appeals to reach agreement on an issue

Objective: a major goal in the study of debate as a method of rhetorical art is to develop one's ability to play from either position with equity. The concept of resolution is therefore to inform participants while refining one's understanding of a topic

Formula: preface, case, evidence, test, result

Principles: independence, substance, synthesis, clarity

Format:
Motion - a viewpoint that is argued for or against
Chair - a person who monitors the debate
Proposer - speaks in favor of the motion
Opposer - speaks against the motion (typically after the proposer has made their speech)
Seconders - two people who speak after the proposer and opposer, one for and one against the motion
Amendments - changes suggested for the main motion. Amendments also require opposers and seconders
Abstain - Voting neither for nor against the motion based on uncertainty or disagreement with both opposing views.
House - the venue where the debate and its members have taken place

Rhetorical Fallacies:
1) Ad hoc- using an unsubstantiated hypothesis to explain away inconsistent facts
ex. 'The suspect is known for foreign hostility and a facility was bombed'
'There is no related evidence'
'Sources are often obstructed'

2) Adverse consequences- exciting dire consequences of an "unfavorable" decision
ex. 'if you challenge the government, the terrorists will win'

3) Affirmation of the consequent
ex. 'if a crime were committed, we would hear a confession. We see no confession, therefore there was no crime'

4) Amphiboly- ambiguous premise
ex. 'conspiracy theorists' ideas fill a personal gap'

5) Anecdotal evidence
[ex. 'there are reports of explosions, therefore there were explosives'

6) Argumentum ad antiquitatem- "it's always been done that way"
ex. 'no covert agency has ever been dissolved by public protest'

7) Argumentum ad baculum- appeal to force
ex. 'if you criticize the official story, you are unpatriotic'

8) Argumentum ad crumenam- money as a criterion of correctness
ex. 'the accused are successful people; why would they commit a crime?'

9) Argumentum ad hominem- personal attack on character
(ex. 'these guys are a bunch of wackos!'

10) Argumentum ad ignorantiam- because it hasn't been proven false
ex. 'you have no reconstructed narrative of the plot'

11) Argumentum ad logicam- assuming something is false because 1 proof is invalid while another may be true
(ex. 'both buildings were monitored by security'

12) Argumentum ad misericordiam- appeal to pity
ex. 'you are offending victim families'

13) Argumentum ad numerum- appeal to a statistic
[ex. '60% of the public doesn’t believe the official story of 9/11'

14) Argumentum ad populum- appeal to public opinion
ex. '60% of the public does believe the official story of 9/11'

15) Argumentum ad verecundiam- appeal to authority or an agreeing opinion, esp. without credence
ex. 'you are not an engineer'

16) Bifurcation- “black and white”
ex. 'you are either with us or the terrorists'

17) Circulus in demonstrando (circular argument)- using what they are trying to prove as part of the proof of that thing
ex. 'the administration couldn’t commit a crime because it's within the government'

18) Complex question- implicitly assuming something to be true by its construction
(ex. 'you don’t believe this was possible?'

19) Composition- assuming a property shared by individual items is also shared by a collection
ex. 'humans are just animals, so why bother with justice?'

20) Converse accident- generalization
ex. 'the Secretary of Transportation was a good man, therefore so is the administration'

21) Converting a conditional
ex. 'if surveillance systems are increased, terrorist activity is seen to decline. So if politically violent attacks increase over the next few years, we'll know that surveillance monitoring should be increased'

22) Cum hocergo propter hoc- if two things occur simultaneously, one must be a cause of the other
ex. 'terrorism has declined since introducing new legislation. Clearly new legislation insures safety'

23) Denial of the antecedent
ex. 'if an individual was filmed in a different circumstance, it would prove that he had other aspects to his identity. However, there is no footage, so other characteristics must be fictional'

24) Dicto simpliciter (sweeping generalization)- expecting a statement to be true in every specific case
ex. 'a bureaucratic plot could not be carried out in secrecy'

25) Division
ex. 'a public representative is employed at a reputable institution, therefore his actions must be reputable'

26) Equivocation- using a word with different meanings in the same argument
(ex. '"pull it" refers to withdrawing a rescue operation'

27) Extended analogy- claiming that situations are analogous to each under a general premise
ex. 'relinquishing civil liberty is as vital as securing domestic safety after an attack'

28) Ignoratio elenchi- irrelevant conclusion
ex. an individual claims that foreign intervention is a necessity yet argues that intervention is beneficial to national morale

29) Naturalistic fallacy- assuming that whatever is consistent with "nature" is good
ex. 'hostility is innately human'

30) Nature, appeal to- derive conclusions about value from statements of fact alone
ex. 'the physics of such collisions are unprecedented'

31) Non causa pro causa- something is identified but not proven to be the cause of an event
ex. 'there was structural damage, fires and the building collapsed. So, damage and fires destroyed the building'

32) Non sequitur- stating something that does not strictly follow from a premise
ex. 'public criticism distracts from legal changes of policy'

33) Petitio principii (begging the question)- when a question has been asked before in the same discussion while a conclusion is reached on a related matter, without the original question being answered
ex. 'since preparing a building for demolition is difficult, it would be impossible'

34) Plurium interrogationum- demand of a simple answer to a complex question
ex. 'did an executive personally plant charges--yes or no?'

35) Post hoc ergo propter hoc- assuming A caused B because A happened prior to B
(ex. '2 buildings fell in the morning, a 3rd building fell that afternoon'

36) Red herring- introducing irrelevant facts or arguments distracting from the question at hand
ex. 'The structures behaved unusually'
'Were you there on that day?'

37) Shifting the burden of proof- assumption that something is true unless proven otherwise
[ex. 'so if you don't think abuse has happened in the government, can you prove it?'

38) Slippery slope- assuming one action will lead to a series of other actions or policies
ex. 'if we don’t defeat opponents abroad, we will lose at home'

39) Straw man- refuting an extremity or caricature
(ex. 'it would require hundreds of conspirators'

40) Undistributed Middle- implication that things are similar, but without specification in what way
ex. ' violent radicalism and religion have histories in politics, so isn't Islam violent?'

Source:
http://www.csun.edu/~dgw61315/dgwdebate.html
http://www.infidels.org/library/modern/mathew/logic.html
http://www.triviumpursuit.com/speech_debate/what_is_debate.php
http://en.wikipedia.org/wiki/Debate