Logic summary.docx

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Transcript of Logic summary.docx

Fallacies

- Certain kind of defect in an argument

An argument can be defective when:

1. It has one or more false premises2. It contains a fallacy

Kinds of fallacy

1. Formal fallacy- Identifies through mere inspection of the form

or structure of an argument- All A are B.

All C are B.Therefore, all A are C

2. Informal Fallacy- Detected only through analysis of the content

of the argument- Makes bad argument appear good- All A are B

All C are DAll A are D

- Backed with the motive of the arguer to deceive the reader/listener and sometime, the arguer deceives even himself

Aristotle

- Identifies 13 fallacies and separated them into 2 groups

FALLACIES OF RELEVANCE

- Premises are logically irrelevant to conclusion- Premises are psychologically relevant so

conclusion seem to follow logically, even though it does not.

- Connection between premises and conclusion is emotional thus it is important to distinguish genuine evidence from forms of emotional appeal

1. APPEAL TO FORCE (ARGUMENTUM AD BACULUM: APPEAL TO THE “STICK”)

- Arguer poses a conclusion to another person and tells the person either implicitly or explicitly that harm will come to him/her if he/she does not accept the conclusion

- Involves threat to physical/psychological being- Accomplishes purpose by psychologically

impeding reader/listener from acknowledging a missing premise that if acknowledged, would be seen as false/questionable

2. APPEAL TO PITY (ARGUMENTUM AD MISERICORDIAM)

- Arguer poses a conclusion and then attempts to provoke pity from reader/listener in the effort for him/her to accept the conclusion

3. APPEAL TO THE PEOPLE (ARGUMETUM AD POPULUM)

- Uses desires to be loved, esteemed, admired, valued etc. to get the reader/listener to accept conclusion

o Direct approach Arguer, addressing a large

group of people, excites emotions and enthusiasm of crowd to win acceptance of his conclusion.

Used by propagandist and demagogue

May be in writing/speakingo Indirect approach

Arguer appeals to one or more individuals separately

Techniques in advertising industry

Under Indirect approach:

Bandwagon argument You will be left out if

you don’t agree to what majority wants

Appeal to vanity Associates product to a

celebrity that is admired, the idea being you too, will be admired if you use it

Appeal to Snobbery