Inference of Authority (A commentator asserts a claim. Evaluate the credibility of your source.)
Access: Did the authority have first hand knowledge of the issue? (A journalist who’s been to Iraq as opposed to one who watched events on TV. A commentator who had done extensive “second-hand” investigation by reviewing literature on the subject might compensate well for lack of first hand knowledge.)
Expertise: Is this an area that the authority has some expertise? Bouknight is a doctor, but he shouldn’t try to remove your appendix. Should we listen to a retired golfer recommend motor oil?
Un-biased: Scientists funded by Phillip-Morris showed that the link between smoking and lung-cancer was not conclusive. Pharmaceutical companies research departments work underneath the marketing team.
If source is biased against your view, this could be very helpful to your argument. Donald Rumsfeld says we can’t measure success in the Iraq War but his boss, George W. Bush says we’re being successful (The Nation, Nov. 21, 2003. p.3) Tip to use this technique: Look for articles opposing your view. Use them respectfully and cite them. Similarly, if the source has something to lose by supporting your view, also a plus. (Jim McDougal sentenced to three years testifying in Whitewater case?)
Inference of Cause and Effect (One event or condition leads to another event.)
Eg: Heat + Fuel + Oxygen = Fire (certainly)
Increased tuition results in fewer students enrolling in college. (probably-- because it’s one causal factor.)
Most effects have more than one cause.
Eg: increases in crime, divorce. Economic recession
Do not confuse correlation (occurrence of one event matches occurrence of another event) with cause, unless there’s more evidence of the relationship.
Eg: There's a general correlation between the availability of abortion and social concern for the well-being of children, as an upcoming publication from the Center for Reproductive Law and Policy (Pollitt, K. “Anti-choice, Anti-Child.” The Nation 15 Nov 1999. p. 15). What is the causal relation?
Inference from Literal Analogy (detailed comparison of two things in the same category)
Eg: Gun Control is greater in England where there is much lower homicide rates; therefore, greater gun control would reduce homicides in the US.
(Arguments for analogy depend upon elaborating the similarities between the two entities being compared. Arguments opposed depend on developing the differences between the two countries.)
Eg: Iraq is George Bush's Vietnam. A draining war against insurgents in a country far away with no clear objectives for our side and indigenous allies who can't be trusted.
Sign Inference (An event or item indicates the presence of some state or other event.)
Eg: Bars on the Window of a house are a sign of crime in the house’s neighborhood.
Eg: Laws against racial discrimination indicate a history of racial discrimination.
Eg: If Radio Marti isn't having an effect on the Cubans it's directed at, why does the Government of Cuba use up 87 million watts a year to jam the Radio Marti signal?
All arguments about a person’s character are sign arguments because you cannot have direct experience of someone’s character, only their behavior.
Arguments from Authority are considered by some to be sign arguments.
Inference from Generalization: (Known examples of a certain category allow us to infer about unknown examples).
Eg: French films have confusing plots, if they even have plots. Most of the French films I’ve seen have suffered from this difficulty. Therefore, avoid French films.
Statistics are often large collections of generalizations:
Sufficient: Are there a sufficient number of known examples used? (Associated Press standards require a sample of 33 before making a statistic!)
Random: Were the examples randomly collected? (Hite report.)
As with Authority, consider source of statistics.