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Make sure you read the lectures and watch the below videos. Use the lecture and videos to write a deductive or inductive argument on climate change. Study all Seven Forms of deductive arguments introduced in your Lecture as well as the inductive types. Try to make a clear and succinct argument rather than a lengthy essay.Watch these videos and read the articles below for food for thought. Some pros and some cons.

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Objectives for this Module:

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Understand the difference between deduction and

induction.

Plus, Validity and soundness; strength and

cogency;

Be able to critically examine arguments for the

said properties.

Be able to demonstrate this in discussions and

written exercises.

Definition: A deductive argument is one where the conclusion

follows necessarily from the premises; and, an inductive

argument is one where the conclusion follows with degrees

of probability from the premises.

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Deductive Arguments: Below is a chart. It shows that

every argument is either Deductive, Inductive or

Fallacious. Deductive arguments have conclusions that

follow necessarily based on the form of reasoning.

Inductive argument have conclusions that follow from

probability and are based on content.

It It is useful to know Deductive common types of

arguments so we can spot them easily: Categorical

Syllogism; Arguments from Math; Arguments by

Definition. You will now learn other forms.

Let’s focus on Deduction first: Study the chart below. The

chart shows that only Deductive arguments can be valid. They

can be invalid, in which case they are either fallacious or fall

outside the class of deductive and are inductive.

Here is the Chart: Chart #1

Every argument is either:

1) Deductive

2) Inductive, or

3) Fallacious

Validity:

VALID >

Deductive

INVALID>

Inductive or

Fallacious

When is it Rational?

Rational> if it is deductive and valid; if it is inductive and

strong.

Irrational> if it is deductive and fallacious; if it is inductive and weak.

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DEFINITION OF VALIDITY: A valid deductive argument is one

where assuming the premises to be true (that is, IF the

premises are true), then the conclusion cannot be false. This is

not the same as saying that it is an argument that has true

premises and true conclusion is valid. The reason is you can

have an argument with true premise and true conclusion that

is invalid on account of bad reasoning. The only condition of

truth and falsity you CANNOT have for validity to obtain is

TRUE premises and FALSE conclusion.

What these charts show you is that you can have a variety of

values for validity except one: that is when the premises are

true and conclusion is false. Then the argument must be

INVALID.

If you have true premises and true conclusion and valid

reasoning, then it is also SOUND. If you have correct

reasoning and false premises and true conclusion or false

premises and false conclusion, you can still be valid but then

you are UNSOUND. From this you should have gathered that

validity is about HOW you reason, whereas soundness is

about the TRUTH and FALSITY of the premises and

conclusion.

Chart #3, from Thinking Well, by S. Kelly.There are seven

valid forms to learn up front. They appear here and below

and are in “Files”. We will practice with some argument

forms that are valid and invalid VALID and INVALID

Below are the definitions of the seven valid forms: Each of

these patterns is deductive and therefore, valid. We will

discuss them and then practice with ordinary language

exercises to identify the forms.

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Modus Ponens means you are affirming the

statement in order to conclude: If A then B, A,

therefore B.

Modus Tollens means you are denying to deny: If A

then B, not B, therefore not A.

Disjunctive Syllogism (argument) means you are

denying the first term to conclude the second term.

Hypothetical Syllogism means if you have A

implying B, and you have B implying C, then A can

imply C.

The basic pattern for Universal Syllogism is the

same as H.S. above, except it is made up of

Categorical Statements (statements containing All,

No, or Some).

Chain Arguments have this form but insert the

premise A, so allows for a conclusion of C.

Predicate Instantiation is a categorical form but it is

quite similar to Modus Ponens. It means the second

premise term shares the predicate because it belongs

to the class.

To help you conceive of what was just explained above,

please read the presentation on “Argument

Strength”. Chart #4: Here is the

link: ArgumentStrengthChart083.pdf

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Now, I would like you know some INVALID forms that

look similar to those above. If you study these you will

notice the similarities in pattern, but these are not

valid forms. You can find these in “Files” again and

find the sheet on INVALID ARGUMENT FORMS. It

appears below:

Chart #5, See below:

InvalidArgumentForms.doc

2) TESTING ARGUMENTS for Validity: We can test

arguments by way of these principles. We can look for a

form (valid or not), and additionally we can do an

INDIRECT TEST. Below you will see how to test Indirectly:

HOW TO TEST ARGUMENTS BY THE INDIRECT TEST

1) Assume true premises.

2) Assume false conclusion.

(Think! Could I have a case of an invalid argument where, if I

assume premises true my conclusion could be false?)

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Read the argument.

If it conforms to true premises and false conclusion,

then it is INVALID. If assuming true premises and

your conclusion CANNOT BE FALSE, then it is

VALID.

When VALID: We will say there is a

CONTRADICTION TO OUR TEST ASSUMPTION,

namely, #1 and 2 above do not occur.

When INVALID: We will say there is NO

CONTRADICTION TO OUR TEST ASSUMPTION,

namely, #1, and 2 occurs.

INDUCTION:

Important: For Inductive Arguments the same relationships

obtain as in the Hurley Chart above. The only difference is you are

testing content based on probability instead of form. The language

used, therefore, will be “Strong” (for Valid) and “Cogent” (for

Sound) as per our text.

Chart #6, Inductive Arguments Chart.

**INDUCTIVE ARGUMENT TYPES: It is useful to know the

Inductive common types of arguments so we can spot them

easily: Prediction predicts and goes beyond the information in

the premises; Cause and Effect argues from cause to effect or

vice versa; Generalization generalizes to all from samples;

Authority brings in an authority to conclude; Analogy

compares properties of different entities to conclude. You can

read about these in chapters 4, 5, 8, 9.

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