REVIEW PT 2
PRACTICE & APPLICATIONS
Fallacies, Again
With a partner, construct:
(6 minutes)

An example of an argument using the straw man
fallacy

An example of an argument using the appeal to
ignorance fallacy

An example of an argument using a false dichotomy
Translation
With a partner, translate (5 minutes):
1.
If health maintenance organizations cut costs, then either
preventative medicine is emphasized or the quality of care
deteriorates.
2.
The ebola virus is deadly, but it will become a threat to
humanity at large if and only if it becomes airborne and a
vaccine is not developed.
3.
It is not the case that both Walmart’s jeopardizing worker
safety implies that Target does and Costco’s treating
workers decently implies that Kmart does.
Translation
With a partner, translate (5 minutes):
1.
If health maintenance organizations cut costs, then either
preventative medicine is emphasized or the quality of care
deteriorates. 𝑪 ⊃ 𝑷 ∨ 𝑸
2.
The ebola virus is deadly, but it will become a threat to
humanity at large if and only if it becomes airborne and a
vaccine is not developed.
3.
It is not the case that both Walmart’s jeopardizing worker
safety implies that Target does and Costco’s treating
workers decently implies that Kmart does.
Translation
With a partner, translate (5 minutes):
1.
If health maintenance organizations cut costs, then either
preventative medicine is emphasized or the quality of care
deteriorates. 𝑪 ⊃ 𝑷 ∨ 𝑸
2.
The ebola virus is deadly, but it will become a threat to
humanity at large if and only if it becomes airborne and a
vaccine is not developed. 𝐷 ⋅ (𝑇 ≡ 𝐴 ⋅ ∼ 𝑉 )
3.
It is not the case that both Walmart’s jeopardizing worker
safety implies that Target does and Costco’s treating
workers decently implies that Kmart does.
Translation
With a partner, translate (5 minutes):
1.
If health maintenance organizations cut costs, then either
preventative medicine is emphasized or the quality of care
deteriorates. 𝑪 ⊃ 𝑷 ∨ 𝑸
2.
The ebola virus is deadly, but it will become a threat to
humanity at large if and only if it becomes airborne and a
vaccine is not developed. 𝐷 ⋅ (𝑇 ≡ 𝐴 ⋅ ∼ 𝑉 )
3.
It is not the case that both Walmart’s jeopardizing worker
safety implies that Target does and Costco’s treating
workers decently implies that Kmart does.
∼
𝑊⊃𝑇 ⋅ 𝐶⊃𝐾
Truth-Functional Properties
Tautologous, Self-Contradictory, or Contingent? (6 MINS)
1.
G⊃(G⊃G)
2.
N⊃(N⊃(N∨O))
3.
( A ⊃ B ) ⋅ ( A ⋅ ~B )
4.
(X⊃(Y⊃Z))≡ ((X⊃Y)⊃Z)
Truth-Functional Properties
Tautologous, Self-Contradictory, or Contingent?
1.
G ⊃ ( G ⊃ G ) tautologous
2.
N ⊃ ( N ⊃ ( N ∨ O ) ) tautologous
3.
( A ⊃ B ) ⋅ ( A ⋅ ~B ) self-contradictory
4.
( X ⊃ ( Y ⊃ Z ) ) ≡ ( ( X ⊃ Y ) ⊃ Z ) contingent
Categorical Propositions
A categorical proposition is a proposition that
relates two classes. These classes are denoted by a
subject term and a predicate term.
“Some zebras are hard to tame.”

What is the subject term?
ZEBRAS

What is the predicate term?
HARD TO TAME
Categorical Propositions
“No scientists are willing to state that they believe Bigfoot
exists.”
What letter proposition is this?
E – “No S are P”
QUALITY: Is this an affirmative or a negative proposition?
NEGATIVE
QUANTITY: Is this a particular or a universal proposition?
UNIVERSAL
Categorical Propositions
IMMEDIATE INFERENCES
CLAIM: Some conservatives are not pro-life.
[An O statement: “Some S are not P.”]
Which of the following is an immediate inference from the
above?
1)
It is false that all conservatives are pro-life.
2)
It is true that no conservatives are pro-life.
3)
It is true that some conservatives are pro-life.
Categorical Propositions
O: Some conservatives are not pro-life.
A: All conservatives are pro-life.

If the O claim is true, the A claim is false, and if
A is true, O is false.

The same holds for E and I…

If the E statement is true, the I statement is false, and
vice versa.
Categorical Propositions: REMINDER

Quality:
 Affirmative:
 All
S are P.
 Some
S are P.
 Negative:
 No
S are P.
 Some
S are not P.
Categorical Propositions: REMINDER

Quantity
 Universal:
 All
 No
S are P.
S are P.
 Particular:
 Some
S are P.
 Some
S are not P.
Categorical Propositions: REMINDER

Letter Names of Propositions:

A: universal affirmative

E: universal negative
 I: particular affirmative

O: particular negative
Categorical Propositions
Study suggestion:
See if you can draw the Modern Square of
Opposition without looking.