Different Types of Reasoning

Reasoning by Analogy: 

• Premise 1: Sharks swim in the ocean and eat fish
• Premise 2: My cousin swims in the ocean
• Conclusion: My cousin eats fish

Sign Reasoning:

• Where there is rain, there are clouds

Casual Reasoning:

• When the fire trucks drive by the house, the dog howls

Reasoning by Criteria:

• The honey glazed ham you cook is always delicious, are you sure you want to try a new turkey recipe?

             (meaning: cook the honey glazed ham)


Reasoning by Example:

• You should get a terrier if you get a dog.  I have a friend who got a terrier and he is the most behaved dog ever.

Inductive:

• Every morning at 9 am, the old man walks his dog.
• Tomorrow morning at 9 am the old man will walk his dog.

Deductive:

• If every human has ten toes, then they have five toes on each foot
• Barry is a human
• Therefore, Barry has ten toes and five on each foot

Valid and Weak Forms of Arguments Using Conditionals

So one thing in Chapter 6 that I read was about valid and weak forms of arguments using conditionals.  In this section of the chapter, Epstein discusses how an argument can be valid, but it can also be weak at the same time.  A direct way of reasoning with conditionals would be: If A, then B, A, Therefore B.  However, an indirect way of reasoning with conditionals would be: If A, then B, not B, Therefore not A.  These structures are seen to be valid forms of arguments, however, there are valid forms that would be considered weak arguments, such as: If A, then B, B, Therefore A  and If A, then B, not A, Therefore not B.  
An example of a weak yet valid argument would be:
If Sally goes shopping, then Hank gets mad.
Hank is mad
Therefore, Sally went shopping


This is valid because when Sally shops Hank gets mad.  However, it is weak because even though Hank is mad, it doesn't necessarily mean that Sally went shopping because that isn't the only reason why Hank ever gets mad.  He could be mad because of another reason.

Raising Objections and Refuting an Argument Directly

In Chapter 7 of Critical Thinking, Epstein explains the idea of raising objections in an argument.  According to Epstein, "Raising objections is a standard way to show that an argument is bad.  In doing so, we are making another argument that either calls into question one of the premises, or shows that an unstated premise is dubious, or illustrates by the argument is weak."  

For instance, the other day I was out shopping with my friend and she found a dress that she thought was adorable and fashion forward.  She claimed that everyone would want that dress, that people will be jealous of her, and that she had to absolutely get the dress.

I simply argued back that I personally wouldn't want the dress and that if everyone would want the dress why would she get it and have everyone match her.

Something else I learned in chapter 7 is refuting and argument directly.  There are specific ways of directly refuting an argument:

• Showing that at least one of the premises is dubious
• Showing that the argument isn't valid or strong
• Showing that the conclusion is false

Even though there are specific rules to go by in order to refute an argument directly, after reading these steps, it is easier now for me to realize how to refute an argument correctly.

Compound Claim and Contradictory of a Claim

In Chapter 6 of Critical Thinking, I learned about what a compound claim was.  According to Epstein, "a compound claim is one composed of other claims, but which has to be viewed as just one claim."  
For example, the other day my friend had borrowed one of my favorite t-shirts.  I told her that she better not stretch it out or spill anything on it because it was one of my favorite shirts.  
She came back at me with, "I'll return it spotless and perfect or else I'll buy you a new one."
In her argument she basically stated that she'll return it to me the way it was or that she would buy me a new one.
Also in chapter 6, I learned about contradictory or a conditional. Meaning, "If A, then B has contradictory A but not B."
An example of a contradictory of a conditional is when I decided to cut my hair.
A Conversation between me and my friend the other day:
Me: I really want to cut my hair short, but when my hair is short my face looks round and fat.
My Friend:  You had your hair cut short before and your face did not look round and fat.
This example shows that my argument was contradicted by my friend's comment because I had my hair cut before and she expressed that my worries are not completely valid, for she told me that my short haircut made my face look fine.

The Mark of Irrationality

The other day I had to go to work around 1 o'clock.  I pulled out of my street on to a fairly busy street where the speed limit is 35 mph.  However, there is a school across the street so when children are present the speed limit drops down to 25 mph.  I was running late to work so I drove down the street according to the usual speed limit of 35 mph and wasn't paying attention to my speedometer what so ever.  As i got to the first light I could see on the right hand side, 6 cops on motorcycles with their binocular radars were picking out specific people to check their speed. 
When the light turned green a cop stepped onto the street, he waved people by and pointed at me and gestured me to pull over.  When he pulled me over he asked if I knew that it was a school zone at the time and that the speed limit was 25, I played stupid and said that I didn't know.  I asked the officer how fast I was going and he claims that I was going 38 mph.  
I was super upset about the fact that he was going to give me a speeding ticket(my first speeding ticket :( ) for only going over the usual speed limit of 35 by 3 mph.  However, this is an example of The Mark of Irrationality.
Even though I knew I was speeding I didn't agree with the fact that I had gotten a ticket.  

Cover Girl

Introducing the three-minute facelift effect*. Start with Simply Ageless Serum Primer. The advanced formula with Olay Regenerist complex helps boost elasticity and smooth skin's appearance for a finish that looks instantly firmed. Then apply Simply Ageless Foundation to cover fine lines and wrinkles. Together, the results are simply amazing! 

* By firming skin's appearance with results not comparable to surgical procedures.

In this advertisement, Cover Girl makes it seem that this new serum they have come up with, basically has the same effects as plastic surgery.  They are supporting the fact that there is a painless and cheaper form of a face-lift.  

The claim is a good one, but it is hard to say if it is valid.  The only way it could be valid is if they used real examples of people who have used the product and actually saw positive results instantly.  However, I personally would believe the claim only because I have used Cover Girl products before and have had great results just like their advertisement had said.

Also, in section B of chapter 5 in Critical Thinking, Epstein states that "We can accept a claim made by someone we know and trust who is an authority of this kind of claim."  Cover Girl has reviews made by doctors that support their claim, therefore, it wouldn't be a bad thing to consider this argument to be one that is true.

Repairing an Argument

The other day I was talking with my sister about how I wanted to watch You've Got Mail.  She expressed that the movie was one of the best movies she has even seen because Tom Hanks was in it.  She claims that no matter what movie Tom Hanks is in, the movie will be really good.

Even though I may agree with her that all Tom Hank movies are good, her argument is not a good one.  She cannot base how good a movie will be just by knowing that Tom Hanks is in the movie.  Even though majority of the films he has starred in have received good ratings, it is impossible to say how good a movie will be without seeing it first.

In order to make this argument a good one, she would have to re-word how she phrased this statement. 

She can re-word the argument so it is a personal comment, "I believe that every movie Tom Hanks is in will be really good."  By making the argument a personal opinion, no one can say that her argument is bad.