∀ {ι : Type u_1} {α : ι → Type u_2} {mα : (i : ι) → MeasurableSpace (α i)}
  {P : (J : Finset ι) → MeasureTheory.Measure ((j : ↥J) → α ↑j)} {s t : Set ((i : ι) → α i)}
  (hP : MeasureTheory.IsProjectiveMeasureFamily P),
  s ∈ MeasureTheory.measurableCylinders α →
    t ∈ MeasureTheory.measurableCylinders α →
      s ⊆ t → (MeasureTheory.projectiveFamilyContent hP) s ≤ (MeasureTheory.projectiveFamilyContent hP) t