Solutions to Easy Proofs in QL
Proof 1
1.
(x)Sx
⊃
(
∃
x)Px
premise
2.
(x)~Px & (
∃
x)Gx
premise
3.
(x)~Px
simp, 2
4.
~(
∃
x)Px
Q.N.R. 3
5.
~(x)Sx
M.T., 1,4
6.
(
∃
x)~Sx
Q.N.R. 5