Description: For sets, the identity relation is the same as equality. (Contributed by NM, 13Aug1995)
Ref  Expression  

Hypothesis  ideq.1   B e. _V 

Assertion  ideq   ( A _I B <> A = B ) 
Step  Hyp  Ref  Expression 

1  ideq.1   B e. _V 

2  ideqg   ( B e. _V > ( A _I B <> A = B ) ) 

3  1 2  axmp   ( A _I B <> A = B ) 