Critical Thinking and Logic (C168)

Which of the following is an example of affirming the consequent fallacy?

If A, then B. B is true. Therefore, A is true.

If A, then B. B is true. Therefore, A is not true.

If A, then B. B is not true. Therefore, A is true.

If A, then B. A is true. Therefore, B is not true.

Argument for why people should not eat meat

Consider the following argument:

1. Z → (M ∧ F)
2. (M ∧ F) → (H ∨ ¬P)
3. ∴ Z → (H ∨ ¬P)

Which rule of inference was used to derive the conclusion in this argument?

Conditional Elimination

Modus Ponens

Conditional Introduction

Modus Tollens

Consider the following argument:

1. (A ∧ B) → C
2. ¬C
3. ∴¬(A ∧ B)

Which rule of inference was used to derive the conclusion in this argument?

Conditional Elimination

Modus Tollens

Conditional Introduction

Modus Ponens

Which relation(s) does the predicate "is a co-worker of" encode?

a.)

Reflexive and transitive

b.)

Symmetrical, transitive and reflexive

c.)

Symmetrical and reflexive

d.)

Symmetrical and transitive

Consider the following:

1. K → (Q ∨ X)
2. (Q ∨ X) → R
3. Q
   .
   .
   ∴ ¬U ∨ (K → R)

Which of the following is a next step working up from the conclusion?

a.)

K → R

b.)

¬U ∨ (K → R)

c.)

¬U

d.)

Q ∨ X