| ∀ vols1, v. # vols1 < # vols0[v0, ebatbl] → true → (v ∈ to-vtbl(vols1) ↔ v ∈ vols1) ⊦ v = v0 ∨ v ∈ to-vtbl(vols0) ↔ v = v0 ∨ v ∈ vols0, v0 ∈ vols0 |
∀ vols1, v. # vols1 < # vols0[v0, ebatbl] → true → (v ∈ to-vtbl(vols1) ↔ v ∈ vols1) ⊦ v ∈ to-vtbl(vols0) ↔ v ∈ vols0, v = v0, v0 ∈ vols0