∀ {X : SSet.Truncated 2}
  {x₀ x₁ x₂ : X.obj (Opposite.op { obj := SimplexCategory.mk 0, property := SSet.Truncated.Edge._proof_1 })}
  {e₀₁ : SSet.Truncated.Edge x₀ x₁} {e₁₂ : SSet.Truncated.Edge x₁ x₂} {e₀₂ : SSet.Truncated.Edge x₀ x₂}
  {x y : e₀₁.CompStruct e₁₂ e₀₂}, x = y ↔ x.simplex = y.simplex