Categorical Syllogisms

Question 1

Define: syllogism.

Answer 1

Any deductive argument in which a conclusion is inferred from two premises.

Question 2

Define: categorical syllogism.

Answer 2

A deductive argument consisting of three categorical propositions that contain exactly three terms, each of which occurs in exactly two of the propositions.

Question 3

Define: standard form.

Answer 3

The form in which a syllogism is said to be when its premises and conclusion are all standard-form categorical propositions (A, E, I, or O) and are arranged in standard order (major premise, then minor premise, then conclusion).

Question 4

Define: major term.

Answer 4

The term that occurs as the predicate term of the conclusion in a standard-form categorical syllogism.

Question 5

Define: minor term.

Answer 5

The term that occurs as the subject term of the conclusion in a standard-form categorical syllogism.

Question 6

Define: middle term.

Answer 6

In a standard-form categorical syllogism (which must contain exactly three terms), the term that appears in both premises but does not appear in the conclusion.

Question 7

Define: mood.

Answer 7

A characterization of categorical syllogisms, determined by the forms of the standard-form categorical propositions it contains. Since there are just four forms of propositions, A, E, I, and O, and each syllogism contains exactly three such propositions, there are exactly 64 moods, each mood identified by the three letters of its constituent propositions, AAA, AAI, AAE, and so on, to OOO.

Question 8

How many different figures can a categorical syllogism have?

Answer 8

Four.

Question 9

In order to completely describe a standard-form syllogism, you must specify its ___ and ___.

Answer 9

mood; figure (e.g. EIO-2)

Question 10

Define: figure.

Answer 10

The position of the middle term in the premises of a standard-form categorical syllogism.

Question 11

How many forms of standard-form syllogism are there?

Answer 11

256.

Question 12

When diagramming a categorical syllogism, be sure to diagram the ___ premise first (if applicable).

Answer 12

universal

Question 13

What are the four formal fallacies?

Answer 13

Rule 1: avoid four terms (fallacy of four terms).
Rule 2: distribute the middle term in at least one premise (fallacy of the undistributed middle).
Rule 3: any term distributed in the conclusion must be distributed in the premises (fallacy of illicit process).
Rule 4: avoid two negative premises (fallacy of exclusive premises).
Rule 5: if either premise is negative, the conclusion must be negative (fallacy of drawing an affirmative conclusion from a negative premise).
Rule 6: from two universal premises no particular conclusion may be drawn (existential fallacy).

Question 14

What are the fifteen valid forms of the standard-form categorical syllogism?

Answer 14

1. AAA-1 (Barbara)
2. EAE-1 (Celarent)
3. AII-1 (Darii)
4. EIO-1 (Ferio)
5. AEE-2 (Camestres)
6. EAE-2 (Cesare)
7. AOO-2 (Baroko)
8. EIO-2 (Festino)
9. AII-3 (Dastisi)
10. IAI-3 (Disamis)
11. EIO-3 (Ferison)
12. OAO-3 (Bokardo)
13. AEE-4 (Camenes)
14. IAI-4 (Dimaris)
15. EIO-4 (Fresison)