Metamath Proof Explorer


Theorem nfcrALT

Description: Alternate version of nfcr . Avoids ax-8 but uses ax-12 . (Contributed by Mario Carneiro, 11-Aug-2016) (New usage is discouraged.) (Proof modification is discouraged.)

Ref Expression
Assertion nfcrALT ( 𝑥 𝐴 → Ⅎ 𝑥 𝑦𝐴 )

Proof

Step Hyp Ref Expression
1 df-nfc ( 𝑥 𝐴 ↔ ∀ 𝑦𝑥 𝑦𝐴 )
2 sp ( ∀ 𝑦𝑥 𝑦𝐴 → Ⅎ 𝑥 𝑦𝐴 )
3 1 2 sylbi ( 𝑥 𝐴 → Ⅎ 𝑥 𝑦𝐴 )