Theorem _hyp_intro_sb ≪ | index | src | ≫

intro_sb的假设无关形式。

theorem _hyp_intro_sb {x: set} (y: set) (G A: wff x):
  $ \nf x G $ >
  $ G \imp A $ >
  $ G \imp \sb y x A $;

Step	Hyp	Ref	Expression
1		imp_tran	(G \imp \fo x A) \imp (\fo x A \imp \sb y x A) \imp G \imp \sb y x A
2		hyp g	\nf x G
3		hyp h	G \imp A
4	2, 3	_hyp_intro_fo	G \imp \fo x A
5	1, 4	ax_mp	(\fo x A \imp \sb y x A) \imp G \imp \sb y x A
6		fo_elim_sb	\fo x A \imp \sb y x A
7	5, 6	ax_mp	G \imp \sb y x A

Axiom use

Logic (ax_mp, ax_1, ax_2, ax_3, ax_gen, ax_4, ax_5, ax_6, ax_7, ax_12)