exact phi_ih h1
case h.e'_2
σ : Instantiation
τ τ' : MetaInstantiation
x : VarName
phi : Formula
phi_ih : phi.metaVarSet = ∅ → sub σ τ phi = sub σ τ' phi
h1 : phi.metaVarSet = ∅
⊢ sub σ τ phi = sub σ τ' phi
no goals