Metamath Proof Explorer


Theorem nfunv

Description: The universal class is not a function. (Contributed by Raph Levien, 27-Jan-2004)

Ref Expression
Assertion nfunv ¬FunV

Proof

Step Hyp Ref Expression
1 nrelv ¬RelV
2 funrel FunVRelV
3 1 2 mto ¬FunV