SSR Lec8 Cr-Th CH5 + CH6

Base rate error?

Conditional probability is being inverted without all the needed information (specificity, sensitivity and Base rate)

What 4 things to consider when in doubt of is it an explanation or an argument?

1. Is the passage about general knowledge? (Then usually explanation)

2. Is the passage about something that (is agreed upon to have) already happened? (then usually explanation)

3. Is it possible to deduce from the context what the writer is trying to achieve? (indicator words, context of publication)

4. Charity—> We would rather assume someone is giving an explanation than that a bad argument is being given.

Reconstruction: completeness?

1. All terms of the conclusion are connected with the premises

2. The premises have a relevant connection

Reconstruction: Parsimony?

Don’t make more assumptions than strictly needed given the context provided.

Reconstruction: Charity

1. We would rather assume someone is giving an explanation than that a bad argument is being given.

What is the desired clarity when reconstructing the argument?

We include all of the argument and nothing but the argument.

What are the 4 concepts of strength of an argument?

Validity, inductive force, deductive soundness, inductive soundness

What should you do with rhetorical questions in argument reconstruction?

Rewrite as a declarative statement

2 rules of thumb for logical streamlining?

1. Where appropriate, rewrite sentences as either conditional or disjunctive sentences.

2. Rewrite generalisations as such: F are G | _ are not-G (with blanks being all, no, some, etc)

What to do with premises which are left implicit by the speaker?

Make them explicit. But only if we can reasonably assume that the speaker did mean this.

What are connecting premises?

Implicit premises made explicit which are needed to make the argument valid.

What can you say of covering generalisations?

E.g.:

(a) If mika is a siamese cat, it has blue eyes.

(b) All siamese cats have blue eyes

1. The special relationship in which they stand is that (b) is a covering generalisation for (a). (We can also say that (a) is an instance of (b), as is common in logic.)

2. Can be both a hard and soft generalisation (b—>a = deductively and inductively respectively)

What can you say about relevance for argument reconstruction?

When a proposition stated by the arguer is irrelevant to the reasoning that delivers the conclusion, that proposition should not be included in a reconstruction of the argument.

How to handle ambiguity in an argument?

Fill in the different possible meanings, evaluate them all individually.

When does vagueness become a problem?

When the actual meaning of a word is vague.

Not when just the possible extensions are vague

How to handle words with vague meanings in argument reconstruction?

Leave them out

When can we make statements about the relative scope of 2 premises?

1. If the one subject is a subgroup of the other subject.

2. If both premises attribute the same feature to their subject

When reconstructing an argument that uses practical reasoning, what does this means and what 2 things should be considered?

1. The argument is made to make people (not) perform a certain action in order to achieve a certain goal.

2. Do to benefits outweigh the costs? and is this the most effective/efficient action for our goal?

What is expected value and how to calculate it?

The expected value is the relative benefit or cost of an action, given the probability of certain events related to that action.

[P(o1) × V(o1)] + [P(o2) × V(o2)] + . . . [P(on) × V(on)]

Technique: refutation by counterexample

Normally, you would use this when you have already determined that the argument is not valid or inductively forceful, and, in an argument commentary, when you wish to explain why the argument is not valid or inductively forceful

How to engage with an argument (needed to criticise well)

one must either

1. show that the argument is neither valid nor inductively forceful.

2. Show or argue that there is no reason to believe one or more of the premises, or that one or more of them is false

3. Show, if it is an inductive argument, that it is defeated by some other argument. Merely pointing out that a term occurring in the argument is vague or value-­ laden is not sufficient.