Translation Questions 1 - 10: (5 marks each 50 marks total) Translate the following ordinary language statements into predicate logic symbolic form. You can use the predicate letters that are provided. Questions #7 - #10 are more advanced, please note the extra instructions for them.
- Ginger is a spice (G, S)
- Jimmy Carter was not an academy award winner. (A)
- Cell phones are not universally admired products. (C, U)
- Some SUVs are not environmentally friendly vehicles. (B, C)
- All whole numbers are either even or odd. (W, E, O)
- Everything that is alive is mortal. (A, M)
Questions #7 - #10 are translations involving relational predicates, overlapping quantifiers, and identity. You can use the predicate letters provided.
- Something destroyed everything. (Dxy: x destroyed y)
- Everyone is a child of someone. (Cxy: x is a child of y)
- Anyone who reads Kant reads Hume. (Rxy: x reads y, k: Kant, h: Hume)
- Stan Lee invented Marvel Comics. (Ixm: x invented Marvel Comics; s: Stan Lee)
Proof of Validity Questions 11-14: (10 marks each) The following 4 arguments are valid. Provide a proof of validity for each argument. You can use the 18 rules of inference, CP, IP, the rules for introducing and removing quantifiers and the Change of Quantifier rules. Questions #13 #14 are more challenging, they involve relational predicates, overlapping quantifiers, and identity.
11.
- ($x) Fx É ($x) (Gx • Hx)
- ($x) Hx É (x) Jx \ (x) (Fx É Jx)
- (x) (Fx É Hx)
- (x) (Fx É Gx) /\ (x) [ Fx É (Gx · Hx)]
- ($x) [Lx · (y) (My É Pxy)] /\ ($x) [Lx · (Mb É Pxb)]
14.
- ~ Lb
- (x) [ Hx É ( Lx · x = b)] /\ ~ Ha
Proving Invalidity Question 15: (10 marks) The following argument is invalid. Show it to be invalid using the finite universe method.
- ($x) (Gx · Lx)
- ($x) (Gx · Hx) /\ (x) (Lx É Hx)
Sample Solution