Metamath Proof Explorer


Theorem lecmii

Description: Comparable Hilbert lattice elements commute. Theorem 2.3(iii) of Beran p. 40. (Contributed by NM, 7-Aug-2004) (New usage is discouraged.)

Ref Expression
Hypotheses pjoml2.1
|- A e. CH
pjoml2.2
|- B e. CH
lecmi.1
|- A C_ B
Assertion lecmii
|- A C_H B

Proof

Step Hyp Ref Expression
1 pjoml2.1
 |-  A e. CH
2 pjoml2.2
 |-  B e. CH
3 lecmi.1
 |-  A C_ B
4 1 2 lecmi
 |-  ( A C_ B -> A C_H B )
5 3 4 ax-mp
 |-  A C_H B