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 Philosophy 103: Introduction to Logic Test on Categorical Syllogisms This test is based on the following notes: Syllogistic Terms Refutation by Logical Analogy Venn Diagrams Syllogistic Fallacies Testing Standard Form Syllogisms To access answers with a non-java enabled browser,  click here:  CATEGORICAL SYLLOGISMS  ANSWERS

I. Logical Analogies (15 points). Attempt to refute the two arguments below by the method of devising a logical analogy. If the argument cannot be refuted, state why.

1. All persons who worry are people who live in the future.

All persons who plan ahead are people who live in the future.
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All persons who plan ahead are persons who worry.

2. Some procrastinators are lazy persons.

No self-actualized persons are lazy persons.
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Some self-actualized persons are not procrastinators.

II. Standard Form Syllogisms (55 points). Test the following arguments for validity by Venn Diagrams and Syllogistic Fallacies.

1. No loving persons are thoughtless persons.

No loving persons are aggressive people.
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No aggressive people are thoughtless persons.

2. No passive individuals are folks who live well.

All self-actualized persons are folks who live well.
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No self-actualized persons are passive individuals.

3. All persons living the life of excellence are open people.

All open people are honest folks.
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All honest folks are persons living the life of excellence

4. Some studious persons are not friendly persons.

All friendly persons are persons who value others.
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Some persons who value others are not studious persons

5. All folks who live well are persons living the good life.

No persons living the good life are passive individuals.
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No passive individuals are folks who live well.

6. All individuals who cherish living are well adjusted people.

All perfect persons are individuals who cherish living.
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Some perfect persons are well adjusted people.

7. Some worriers are folks who live well.

Some passive individuals are not worriers.
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Some passive individuals are folks who live well.

8. All people cherishing living are persons living excellent lives.

All folks who live well are people cherishing living.
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All folks who live well are persons living excellent lives.

9. All responsive individuals are considerate persons.

All persons who act before they think are responsive individuals.
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All persons who act before they think are considerate persons.

10. All persons who seek fulfillment are persons who take risks.

No shy persons are persons who seek fulfillment.
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No shy persons are person who take risks.

11. All persons living excellent lives are persons cherishing living.

All folks who live well are persons cherishing living.
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All folks who live well are persons living excellent lives.

III. Syllogistic Arguments (30 points). Put the following arguments into standard form and order categorical syllogisms. Name the mood and figure, and test for validity by Venn Diagrams and the Syllogistic Fallacies.

1. No persons who plan ahead are persons who live in the present, since all persons who live in the present are satisfied people, and no persons who plan ahead are satisfied people.

MOOD and FIGURE:

2. No thing is better than being successful, but all doing poorly is better than no thing, so all doing poorly is better than being successful.

MOOD and FIGURE:

3. No self actualized persons are lazy people, and some self actualized persons are happy people, hence some lazy people are not happy people.

MOOD and FIGURE:

IV. Sorities (Optional 10 points). Can you state a sequence of interlocking valid arguments from Parts I-III of this test? If so, restate that argument below.

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