Metamath Proof Explorer


Axiom ax-10d

Description: Distinct variable version of axc11n . (Contributed by Mario Carneiro, 14-Aug-2015)

Ref Expression
Assertion ax-10d ( ∀ 𝑥 𝑥 = 𝑦 → ∀ 𝑦 𝑦 = 𝑥 )

Detailed syntax breakdown

Step Hyp Ref Expression
0 vx ⊢ 𝑥
1 0 cv ⊢ 𝑥
2 vy ⊢ 𝑦
3 2 cv ⊢ 𝑦
4 1 3 wceq ⊢ 𝑥 = 𝑦
5 4 0 wal ⊢ ∀ 𝑥 𝑥 = 𝑦
6 3 1 wceq ⊢ 𝑦 = 𝑥
7 6 2 wal ⊢ ∀ 𝑦 𝑦 = 𝑥
8 5 7 wi ⊢ ( ∀ 𝑥 𝑥 = 𝑦 → ∀ 𝑦 𝑦 = 𝑥 )