1. BUS 290: Critical Thinking for Managers
Text Table of Contents #11:
How Good is the Evidence? Rival Causes

2. Some Comments Faithfulness and Charity in analyzing an argument.
Ambiguities
Why is identifying them important?
Faithfulness and Charity in analyzing an argument.
Context is important in interpreting what the author is communicating.
Evaluating the argument / reasons: use caution
Usually will NOT “Fail” a reason outright.
Usually we will decide on a level of “confidence” in the reason – a degree of probability / acceptance.

3. Testing Arguments and Reasons
Truth – is it true (by common knowledge) or at least probably true?
For example, as we have to assume more things to accept a reason as true – the likelihood of the reason being acceptable decreases.
Logical strength – if the reason is true could we conclude otherwise?
Could these reasons lead to a different conclusion?
Relevance – do we need the reason for the conclusion to be true?
Could different reasons lead to this conclusion?
Circularity – does the conclusion assume or include the reason(s)?

4. Evaluating the Argument
ConcL: I have earned an A in this class.
R1: I have attended every class and completed every assignment and exam.
R2: I have put in more effort than in any other class this semester.
R3: I have an A average for all criteria on the syllabus including assignments and exams.

5. Testing Arguments and Reasons
I like all democrats
Obama is a democrat
Therefore I like Obama
What is the relative degree of relevance of the reasons to the conclusion?
If there was only one other reason I could like Obama – for example I might like him because he takes the same position as I do on something important?
If there were 10 other reasons I might like Obama like his youth, his integrity, his voting record, etc.?
Circularity?

6. How Good is the Evidence: Rival Causes
A plausible alternative explanation for why an outcome occurred.
Applies to:
Reasons related to the conclusion
Evidence / supporting reasons related to main reason.
Ex: muffler problem
concluded vibration caused by broken baffles
but could have been caused by loose bracket, etc.

7. How Good is the Evidence: Rival Causes
Oversimplification: in many situations there are complicated causal relationships.
Research – difficult to account for all differences between the groups studied.
Causation vs. correlation.
When you identify possible alternative causes test them for logical strength and probability.
Ex: Researchers identify alternates in order to support their own conclusions.

8. How Good is the Evidence?
Form groups of 4-5, take out paper and write down all members’ names.
Gun control is like trying to reduce drunk driving by making it tougher for sober people to own cars.

9. Analogy as Evidence
Gun control is like trying to reduce drunk driving by making it tougher for sober people to own cars.
Gun control as typically discussed makes owning
some weapons impossible (like assault rifles) for all people
all weapons hard or impossible for some people (like crazy people or felons).
Does affect non-criminals - for some weapons.

10. I was recently hired to find the best cherry pie recipe in the state of Virginia. I found it in the kitchen of Evelyn Smith. My search began by requesting all interested cherry pie tasters to answer my newspaper ad. All respondents in the state met in a central location and tasted cherry pies. Each of 68 persons tasted the five cherry pies that were judged superior at the recent Virginia State Fair. To assure fairness, each "taste" was made on a different day so that the taste buds would not be confused. The winner? Ms. Smith’s pie! She received over 40 percent of the votes. Her closest competitor received 22 percent. Apparently, Ms. Smith has something special when it comes to cherry pies.

11. According to a recent study, one of the major causes of violence in schools is listening to aggressive heavy metal music. Researchers studied more than 100 cases of “serious” violence within schools and found that 68% of the children involved in the violence listened to heavy metal music. These children would frequently come to school with headphones, listening to this music, as well as wearing clothing from heavy metal bands. Frequently, these heavy metal songs discuss violence, and therefore are a direct cause of school violence.