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Metamath Proof Explorer


Theorem nvel

Description: The universal class does not belong to any class. (Contributed by FL, 31-Dec-2006)

Ref Expression
Assertion nvel ¬ V ∈ 𝐴

Proof

Step Hyp Ref Expression
1 vprc ¬ V ∈ V
2 elex ( V ∈ 𝐴 → V ∈ V )
3 1 2 mto ¬ V ∈ 𝐴