Tutorial 15: Elementary derivations in predicate logic

Logical System

2013

The Tutorial

The sentential rules of derivation carry over unchanged into Predicate Logic

 

 


Exercises to accompany Predicate Tutorial 5

Exercise 1 (of 1).

 

The sentential rules of inference are used unchanged in predicate logic.

Derive

a) Fa ∴ ∼ ∼ Fa
b) ∴ ∼ (Fb& ∼ Fb)
c) ∼ Fm& ∼ Gn∴ ∼ (Fm∨Gn)
d) (Fa&Fa)∨(Gb&Gb)∴ Fa∨Gb
e) Fb⊃(Ga⊃Hc), Fb⊃Ga ∴ Fb⊃Hc
f) Fa∨Gb, Gb⊃Hd ∴ ( ∼ Fa⊃Hd)
g) (Fa⊃Gb)&(Gb⊃Fa) ∴ Fa≡Gb