Phi 270 F03 test 3
Analyze the sentences below in as much detail as possible using only connectives; that is, you should not identify components that are individual terms (or predicates or functors). Present the result in both symbolic and English notation. Be sure that the unanalyzed components of your answer are complete and independent sentences; also try to respect any grouping in the English.
1. If it was cloudy, Bob didn’t see the eclipse
answer
2. Unless the lock is broken, you can get in only if you have a key
answer
Use derivations to checkwhether each of the entailments below holds. You may use detachment and attachment rules. If an entailment fails, present a counterexamplethat divides an open gap.
3. A  → ¬ C, B  → C ⇒ A  → ¬ B
answer
4. (A ∧ B)  → C ⇒ B  → (¬ C  → A)
answer
Analyze the sentence below in as much detail as possible. In this case you should identify components that are individual terms, predicates, or functors. Be sure that the unanalyzed components of your answer are independent (in particular, that none contains a pronoun whose antecedent is in another).
5. If Sam asked Tom to drive him to the meeting, then he is the person who called earlier
answer
6. Dave’s father called the mother of the child who hit him
answer
Use a derivation to show that the entailment below holds. You may use detachment and attachment rules.
7. a = b ∧  Rac ⇒ fa = c → Rb(fb)
answer

Phi 270 F03 test 3 answers
1. If it was cloudy, Bob didn’t see the eclipse
it was cloudy  → Bob didn’t see the eclipse
it was cloudy → ¬ Bob saw the eclipse
C  → ¬ S
if C then not S
C: it was cloudy; S: Bob saw the eclipse
2. Unless the lock is broken, you can get in only if you have a key
¬ the lock is broken  → you can get in only if you have a key
¬ the lock is broken → (¬ you can get in ← ¬ you have a key)
¬ B  → (¬ G ← ¬ K)
¬ B → (¬ K → ¬ G)
if not B then if not K then not G
B: the lock is broken; G: you can get in; K: you have a key
3.
│A  → ¬ C 2
│B  → C 3
├─
││A (2)
│├─
2 MPP ││¬ C (3)
3 MTT ││¬ B (4)
││●
│├─
4 QED ││¬ B 1
├─
1 CP │A  → ¬ B
4.
│(A ∧ B)  → C 3
├─
││B (4)
│├─
│││¬ C (3)
││├─
3 MTT │││¬ (A ∧ B) 4
4 MPT │││¬ A
│││
││││¬ A
│││├─
││││○ ¬ A, B, ¬ C ⇏ ⊥
│││├─
││││⊥ 5
││├─
5 IP │││A 2
│├─
2 CP ││¬ C → Α 1
├─
1 CP │B  → (¬ C  → A)
ABC(AB)C/B(¬C A)
FTFFTF
5. If Sam asked Tom to drive him to the meeting, then he is the person who called earlier
Sam asked Tom to drive him to the meeting → Sam is the person who called earlier
[ _ asked _ to drive _ to _ ] Sam Tom Sam the meeting → Sam = the person who called earlier
Astsm  → s = p
A: [ _ asked _ to drive _ to _ ]; m: the meeting; p: the person who called earlier; s: Sam; t: Tom
6. Dave’s father called the mother of the child who hit him
[ _ called _ ] Dave’s father the mother of the child who hit Dave
C([ _’s father] Dave)([the mother of _ ](the child who hit Dave))
C(fd)(m([the child who hit _ ]d))
C(fd)(m(hd))
C: [ _ called _ ]; d: Dave; f: [ _’s father]; h: [the child who hit _ ]; m: [the mother of _ ]
7.
│a = b ∧  Rac 1
├─
1 Ext │a = b a-b, c, fa-fb
1 Ext │Rac (3)
││fa = c a-b, c-fa-fb
│├─
││ ●
│├─
3 QED= ││Rb(fb) 2
├─
2 CP │fa = c → Rb(fb)