{φ : Prop} →
  {σs : List (Type u)} →
    {P : Std.Do.SPred σs} →
      {motive : Std.Do.SPred.Tactic.PropAsSPredTautology φ P → Sort u_1} →
        (t : Std.Do.SPred.Tactic.PropAsSPredTautology φ P) → ((iff : φ ↔ ⊢ₛ P) → motive ⋯) → motive t