case forall_ x phi phi_ih =>
  unfold sub at h1
  unfold IsMetaVarOrAllDefInEnv at h1
  unfold IsMetaVarOrAllDefInEnv
  exact phi_ih h1
E : Env
σ : Instantiation
τ : MetaInstantiation
x : VarName
phi : Formula
phi_ih : IsMetaVarOrAllDefInEnv E (sub σ τ phi) → IsMetaVarOrAllDefInEnv E phi
h1 : IsMetaVarOrAllDefInEnv E (sub σ τ (forall_ x phi))
⊢ IsMetaVarOrAllDefInEnv E (forall_ x phi)
no goals