Theorem eqerd ≪ | index | src | ≫

theorem eqerd (G: wff) (a: nat) (p: wff) {x: nat}:
  $ G -> a = x -> p $ >
  $ G -> p $;

Step	Hyp	Ref	Expression
1		ax_6	E. x x = a
2		eqcom	x = a -> a = x
3		hyp h	G -> a = x -> p
4	2, 3	syl5	G -> x = a -> p
5	4	eexd	G -> E. x x = a -> p
6	1, 5	mpi	G -> p

Axiom use

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