exact h1_ih_2 V
D : Type
I : Interpretation D
E : Env
F F' h1_phi h1_phi' h1_phi'' : Formula
a✝¹ : AlphaEqv h1_phi h1_phi'
a✝ : AlphaEqv h1_phi' h1_phi''
h1_ih_1 : ∀ (V : VarAssignment D), Holds D I V E h1_phi ↔ Holds D I V E h1_phi'
h1_ih_2 : ∀ (V : VarAssignment D), Holds D I V E h1_phi' ↔ Holds D I V E h1_phi''
V : VarAssignment D
⊢ Holds D I V E h1_phi' ↔ Holds D I V E h1_phi''
no goals