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Thinking

Chapter 1: An Overview

Reasoning Types

Reasoning is a cognitive process that involves drawing conclusions, making judgments, or forming inferences based on facts or premises. This process has been explored from various perspectives:

Reasoning (Book)

Nature of reasoning

Purpose of reasoning

Creativity & Reasoning

Creativity is a major component in reasoning. The process of trying to think of alternative explanations of a set of facts, is an entirely creative process.

Argument Analysis

argument_structure

The 7 steps in argument analysis overview

The steps are not highly technical in itself, the difficult thing is to follow them carefully and skillfully.

  1. Clarification of meaning (of the argument and of its components)
  2. Identification of conclusions (stated and unstated)
  3. Portrayal of structure
  4. Formulation of (unstated) assumptions (the “missing premises “)
  5. Criticism of the premises (given and missing) and the inferences
  6. Introduction of other relevant arguments
  7. Overall evaluation of this argument in the light of 1 through 6

Step 1. Clarification of meaning (of the argument and of its components)

Method

A. Read most or all of the argument of passage under consideration before trying any clarification.

B. Replace unknown terms by reference to a dictionary.

C. Rewrite any unclear parts, using clearer language.

D. In particular, identify vague or ambiguous terms that you suspect the argument is ‘exploiting’.

E. Write out any important unstated but intended implications or suggestions of the premises, the conclusions, and the argument as a whole.

F. Ask yourself if you really understand how everything fits together. In other words, have you a “feeling” for the argument or passage as a whole (even if you don’t accept it)?

Remember

Step 2. Identification of conclusions (stated and unstated)

Method

A. Some of the unstated conclusions turn up in step 1(E) while you’re trying to get the meaning straight. Set them out now; write them in below the passage of text, or fit them in (perhaps in the margin) where they come in. Are there any more, perhaps unintended but unavoidable ones? Get them all states clearly and fairly. Which are the most important ones? Is there one main conclusion? (there usually is.).

B. To located the stated conclusions, look for indicate words like therefore, because, so and thus and for replacement cues such as the location d the end of a paragraph.

C. Notice that here may be several conclusions in the argument, each building on the previous ones. And a passage may also contain several entirely separate arguments.

D. Within any one argument, try to decide if that argument has a main conclusion (or conclusions) and if the others can be ranked as to their importance.

Step 3. Portrayal of structure

Set out the relationships between conclusions and premises (in the parts of the passage that are arguments). You’ve already identified the conclusions. Now you just need to ask yourself what assertions are being put forward to support each of these conclusions. These are the premises. Typically, there will be other material in the passage that is neither a premise or a conclusion. It may be instructions, rhetoric, repetition, flourish, or other statements. The following procedure is unnecessary for simple arguments, and it should be applied to very long ones a page or paragraph at a time.

Method

A. Number each separate assertion; note that one sentence may contain several assertions.

B. Do not give a number to repetitions of the same assertion.

C. Do not number irrelevant statements (“asides”). Remember that your judgments or irrelevance or repetitiousness. Remember that your judgement of irrelevance or repetitiousness are crucial to your evaluation of the argument, and you must be ready to defend them.

D. Do give a number to the implicit conclusions you first located in 1E and 2A.

E. Set out the relationships between the relevant assertions in a tree diagram like the one shown here. It is read downward on the page.

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If 1 and 2 are claims put forward to support 3 and are not themselves supported by any other assertion, and if 3 is supposed to support 4, but not vice-versa, the diagram looks like the illustration. If 4 might be an unstated conclusion, you might put it in parentheses, as shown.

F. For a “balance of considerations” argument, where we say that 1, 2, and 3 suggest the conclusion 5, “Despite” 4 (which points the other way), use symbolism as shown in this diagram.

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G. Sometimes, you can set the structure out on a single line, e.g., ( 1 + 2 + 3 + 4) -> 5 or 1 -> 2 -> ( 3 + 4 ). The arrow then stands for “implies”. Sometimes the suggestion is made that, for example, ( 1 + 2 ) imply ( 3 + 4 ) and are implied by them then use a double-ended arrow, thus: ( 1 + 2 ) <-> ( 3 + 4 ).

H. Terminology: IF statement 1 implies statement 2, we can also say 2 “follows from” 1, or “is a consequence” of 1, or that we can infer 2 from 1. It is incorrect to say 1 infers 2: statements imply but can’t infer; people can do both (but not at the same time).

I. While doing this, begin to look for places where there are significant, unstated assumptions (“missing premises”). You can locate them by adding circles to the tree diagram with letters in them at the appropriate places, thus:

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(A is an assumption that is needed to support the interference from 1 and 2 to 3) To formulate them exactly, see the next section.

Step 4. Formulation of (unstated) assumptions (the “missing premises “)

The most difficult part of reconstructing an argument is fair and clear formulation of the “missing premises”, the unstated assumptions. You must distinguish between:

A. The Arguer’s assumptions, what he or she consciously assumed or would accept as an assumption if asked.

B. The minimal assumptions of the argument whatever is, logically speaking, necessary to make it possible to get from the premises to the conclusion of the arguer.

C. The optimal assumptions, usually stronger claims than B which are logically adequate and independently well-supported.

Step 5. Criticism of the premises (given and missing) and the inferences

Criticism of expression is already covered in 1(g).

Criticizing an inference from statement 1 to statement 2 means criticizing the claim that 1 supports 2. You do not need to know where 1 is true or not in order to consider whether it supports 2. You just have to ask, if 1 were true, wouldn’t 2 then have to be true, or at least very likely be true?

(Understanding this point is also the key to testing a hypothesis, for when we say, “If Jones did kill Mrs. Robinson, he would have to run a mile in 5 minutes to be in the restaurant by 9:10 PM” we’re not saying he did or that he didn’t, but we are suggesting that it’s reasonable to infer from the claim that he did it to a certain conclusion. By checking on whether he could run this fast, we are testing the hypothesis that Jones was the murderer)

Criticizing a premise requires that, if the argument is going to be any good as a way of marshaling support, the forces it calls up had better be strong, i.e., the premises must be reliable. When the premises are technical claims, you aren’t expected to comment on them in the course of logical analysis. When they are definitions or analyses subject to logical criticism, or matters of common knowledge, you are expected to asses them.

Good criticism of an argument requires that you look at both the reliability of the interference and the reliability if the premises. You might think that there’s no point in looking at the interference if the premises are false. But your criticism of the premises may be either in error or fairly easy met by minor modifications; you must guard yourself against this by covering both types of criticism. Good criticism also involves selective attack; first attack the main conclusions (via the premises and interferences that bear on them), and spend less time on the others. And attack with your strongest weapons first do not start by making picky points, following the order of the statements in the original. Start in on the key weaknesses: start with your strongest criticism. Strong criticisms are those that could not be met except by extreme modification or complete capitulation.

Criticism Strategy involves the key move of “counter exampling”. It applies to many types of premise and all types of inference, and it is an exercise in imagination. Here’s an outline of the procedure that you can refer back to later. It may hard to follow in this brief summary, but we’ll explain it with examples in the next section.

Remember!

If you have extensively reconstructed an argument by filling in so many missing premises and conclusions, you will have done so partly by asking what it would take to make a good argument. Hence you often won’t find much to criticize about in the inferences in the reconstructed argument - your criticism will fall instead on the extra bolstering premises you had to add.

Step 6. Introduction of other relevant arguments

If you stopped after Step 5, you’d have a thorough critique and sometimes that’s all that’s called for, but you wouldn’t know what to think yourself. For to discover that a particular argument has some defects is not to discover that it shouldn’t be given some weight, perhaps a good deal. Perhaps, enough to act on. At this point, then, you must step backward and try to get a perspective on the argument. First, ask yourself wether there are arguments on the same issue which point in another direction, perhaps to the opposite conclusion or to a somewhat different conclusion. (In the case of argument from analogy, you may find that the very same analogy can be viewed somewhat differently and taken to support the opposite conclusion.) next, look for the other arguments that support the same conclusion.

Step 7. Overall evaluation of this argument in the light of 1 through 6

Go back to your criticisms. How devastating are they? Could they be met by modest modifications or the original material? Even when devastating, do they cover all the original lines or argument? Look at the results of Step 6. They not only should help you decide what you think but they also may help you to see what the original argument was after. Have you overcritizied it? Now, make your final judgement on the argument. Grade it, in several dimensions if you like, but then make yourself give an overall grade. It’s a cop-out not to. You must decide where it does have force, and how much for you.

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