Metamath Proof Explorer


Theorem hblemg

Description: Change the free variable of a hypothesis builder. Usage of this theorem is discouraged because it depends on ax-13 . See hblem for a version with more disjoint variable conditions, but not requiring ax-13 . (Contributed by NM, 21-Jun-1993) (Revised by Andrew Salmon, 11-Jul-2011) (New usage is discouraged.)

Ref Expression
Hypothesis hblemg.1 ( 𝑦𝐴 → ∀ 𝑥 𝑦𝐴 )
Assertion hblemg ( 𝑧𝐴 → ∀ 𝑥 𝑧𝐴 )

Proof

Step Hyp Ref Expression
1 hblemg.1 ( 𝑦𝐴 → ∀ 𝑥 𝑦𝐴 )
2 1 hbsb ( [ 𝑧 / 𝑦 ] 𝑦𝐴 → ∀ 𝑥 [ 𝑧 / 𝑦 ] 𝑦𝐴 )
3 clelsb3 ( [ 𝑧 / 𝑦 ] 𝑦𝐴𝑧𝐴 )
4 3 albii ( ∀ 𝑥 [ 𝑧 / 𝑦 ] 𝑦𝐴 ↔ ∀ 𝑥 𝑧𝐴 )
5 2 3 4 3imtr3i ( 𝑧𝐴 → ∀ 𝑥 𝑧𝐴 )