Theorem pim2im | index | src |

theorem pim2im {x y: nat} (p1 q1: wff x) (p2 q2: wff y):
  $ A. x (p1 -> (P. y p2 -> q1 -> q2)) -> (P. x p1 -> q1) -> (P. y p2 -> q2) $;
StepHypRefExpression
1 eexb
E. x p1 -> (P. y p2 -> q2) <-> A. x (p1 -> (P. y p2 -> q2))
2 impim
(P. y p2 -> q1 -> q2) -> q1 -> (P. y p2 -> q2)
3 2 imim2i
(p1 -> (P. y p2 -> q1 -> q2)) -> p1 -> q1 -> (P. y p2 -> q2)
4 3 a2d
(p1 -> (P. y p2 -> q1 -> q2)) -> (p1 -> q1) -> p1 -> (P. y p2 -> q2)
5 4 al2imi
A. x (p1 -> (P. y p2 -> q1 -> q2)) -> A. x (p1 -> q1) -> A. x (p1 -> (P. y p2 -> q2))
6 1, 5 syl6ibr
A. x (p1 -> (P. y p2 -> q1 -> q2)) -> A. x (p1 -> q1) -> E. x p1 -> (P. y p2 -> q2)
7 6 com23
A. x (p1 -> (P. y p2 -> q1 -> q2)) -> E. x p1 -> A. x (p1 -> q1) -> (P. y p2 -> q2)
8 7 impd
A. x (p1 -> (P. y p2 -> q1 -> q2)) -> E. x p1 /\ A. x (p1 -> q1) -> (P. y p2 -> q2)
9 8 conv pim
A. x (p1 -> (P. y p2 -> q1 -> q2)) -> (P. x p1 -> q1) -> (P. y p2 -> q2)

Axiom use

axs_prop_calc (ax_1, ax_2, ax_3, ax_mp, itru), axs_pred_calc (ax_gen, ax_4, ax_5, ax_6, ax_7, ax_10, ax_12)