Metamath Proof Explorer


Theorem ltnri

Description: 'Less than' is irreflexive. (Contributed by NM, 18-Aug-1999)

Ref Expression
Hypothesis lt.1
|- A e. RR
Assertion ltnri
|- -. A < A

Proof

Step Hyp Ref Expression
1 lt.1
 |-  A e. RR
2 ltnr
 |-  ( A e. RR -> -. A < A )
3 1 2 ax-mp
 |-  -. A < A