-- Mathlib/Algebra/Module/Torsion.lean
theorem supIndep_torsionBySet_ideal (hp : (S : Set ι).Pairwise fun i j => p i ⊔ p j = ⊤) :
    S.SupIndep fun i => torsionBySet R M <| p i :=
  fun T hT i hi hiT => by
  rw [disjoint_iff, Finset.sup_eq_iSup,
    iSup_torsionBySet_ideal_eq_torsionBySet_iInf fun i hi j hj ij => hp (hT hi) (hT hj) ij]
  have := GaloisConnection.u_inf
    (b₁ := OrderDual.toDual (p i)) (b₂ := OrderDual.toDual (⨅ i ∈ T, p i)) (torsion_gc R M)
  dsimp at this ⊢
  rw [← this, Ideal.sup_iInf_eq_top, top_coe, torsionBySet_univ]
  intro j hj; apply hp hi (hT hj); rintro rfl; exact hiT hj

Proof state:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
⊢ (fun i => torsionBySet R M ↑(p i)) i ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i) = ⊥

Tactic:
have := GaloisConnection.u_inf
  (b₁ := OrderDual.toDual (p i)) (b₂ := OrderDual.toDual (⨅ i ∈ T, p i)) (torsion_gc R M)

Result:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this :
  torsionBySet R M ↑(OrderDual.ofDual (OrderDual.toDual (p i) ⊓ OrderDual.toDual (⨅ i ∈ T, p i))) =
    torsionBySet R M ↑(OrderDual.ofDual (OrderDual.toDual (p i))) ⊓
      torsionBySet R M ↑(OrderDual.ofDual (OrderDual.toDual (⨅ i ∈ T, p i)))
⊢ (fun i => torsionBySet R M ↑(p i)) i ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i) = ⊥

Proof state:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this :
  torsionBySet R M ↑(OrderDual.ofDual (OrderDual.toDual (p i) ⊓ OrderDual.toDual (⨅ i ∈ T, p i))) =
    torsionBySet R M ↑(OrderDual.ofDual (OrderDual.toDual (p i))) ⊓
      torsionBySet R M ↑(OrderDual.ofDual (OrderDual.toDual (⨅ i ∈ T, p i)))
⊢ (fun i => torsionBySet R M ↑(p i)) i ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i) = ⊥

Tactic:
dsimp at this ⊢

Result:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
⊢ torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i) = ⊥

Proof state:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
j : ι
hj : j ∈ T
⊢ i ≠ j

Tactic:
rintro rfl

Result:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
hj : i ∈ T
⊢ False

Proof state:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
⊢ torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i) = ⊥

Tactic:
rw [← this, Ideal.sup_iInf_eq_top, top_coe, torsionBySet_univ]

Result:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
⊢ ∀ i_1 ∈ T, p i ⊔ p i_1 = ⊤

Proof state:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
⊢ ∀ i_1 ∈ T, p i ⊔ p i_1 = ⊤

Tactic:
intro j hj

Result:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
j : ι
hj : j ∈ T
⊢ p i ⊔ p j = ⊤

Proof state:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
⊢ Disjoint ((fun i => torsionBySet R M ↑(p i)) i) (T.sup fun i => torsionBySet R M ↑(p i))

Tactic:
rw [disjoint_iff, Finset.sup_eq_iSup,
  iSup_torsionBySet_ideal_eq_torsionBySet_iInf fun i hi j hj ij => hp (hT hi) (hT hj) ij]

Result:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
⊢ (fun i => torsionBySet R M ↑(p i)) i ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i) = ⊥

Proof state:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
hj : i ∈ T
⊢ False

Tactic:
exact hiT hj

Result:
no goals

Proof state:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
j : ι
hj : j ∈ T
⊢ p i ⊔ p j = ⊤

Tactic:
apply hp hi (hT hj)

Result:
R : Type u_1
M : Type u_2
inst✝² : CommSemiring R
inst✝¹ : AddCommMonoid M
inst✝ : Module R M
ι : Type u_3
p : ι → Ideal R
S : Finset ι
hp : (↑S).Pairwise fun i j => p i ⊔ p j = ⊤
T : Finset ι
hT : T ⊆ S
i : ι
hi : i ∈ S
hiT : i ∉ T
this : torsionBySet R M ↑(p i ⊔ ⨅ i ∈ T, p i) = torsionBySet R M ↑(p i) ⊓ torsionBySet R M ↑(⨅ i ∈ T, p i)
j : ι
hj : j ∈ T
⊢ i ≠ j