Unit 3: Syllogisms and Validity Flashcards Preview

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Flashcards in Unit 3: Syllogisms and Validity Deck (23)
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1

Define argument

A set of statements,

one of which appears to be implied or supported

by the others

2

The _____________ of an argument is the statement that appears to be implied by the other statements in the argument, which are called ____________.

conclusion

premises

3

Define syllogism

A deductive argument

with two premises and three terms

4

What is a categorical syllogism?

A syllogism consisting of

three statements

in categorical form

5

What is the major term of a syllogism?

The predicate of the conclusion

and is used in one premise

6

What is the minor term of a syllogism?

The subject of the conclusion

and is used in the other premise

7

What is the middle term of a syllogism?

The term that is found once in each premise

8

What is the major premise?

The premise that contains the major term

9

What is the minor premise?

The premise that contains the minor term

10

What are the 5 steps

to put a syllogism into standard form?

1. Find the conclusion

2. Find the major term

3. Find the major premise

4. Find the minor premise

5. Write the syllogism in standard order

11

The ____________ of a syllogism

is a representation of it, having statements in standard order with standard abbreviations of its terms.

schema

12

The _________ of a syllogism

is a three-letter description of the types of categorical statements it contains when arranged in standard order

mood

13

The __________ of a syllogism

is the number from 1 to 4

identifying the placement of its middle term

figure

14

A syllogism is __________

if and only if

the premises imply the conclusion

valid

15

A _______________ to a syllogism

is a syllogism of the same form as the original,

but with obviously true premises

and an obviously false conclusion,

in order to show the original to be invalid.

counterexample

16

What is a distributed term?

A term that refers to all members of its category

17

What term is distributed in the following statements: All S are P

No S are P

Some S are P

Some S are not P

All S are P - S is distributed

No S are P - Both S and P

Some S are P - Both are undistributed

Some S are not P - P is distributed

18

What are the 5 rules for testing the validity of syllogisms?

1. Middle term distributed in at least one premise.

2. Distributed in conclusion, then distributed in premise.

3. Cannot have two negative premises.

4. Cannot have a negative premise and affirmative conclusion.

5. Cannot have two affirmative premises and a negative conclusion.

19

What is the Fallacy of the Undistributed Middle?

When the middle term is undistributed in both premises, then no necessary connection is being made between the premises.

20

What is the Fallacy of an Illicit Major?

If the major term is distributed in the conclusion, but not in the premise.

21

What is the Fallacy of the Illicit Minor?

If the minor term is distributed in the conclusion, but not in the premise.

22

What is the Fallacy of Two Negative Premises?

Any syllogism that has only E or O statements as premises.

23

What is the Fallacy of Two Affirmative Premises and a Negative Conclusion?

One premise has to be negative if you have a negative conclusion.