let AFV be WeakAffVect; :: thesis: for a, b, p being Element of AFV st a,b '||' p,p holds
a = b
let a, b, p be Element of AFV; :: thesis: ( a,b '||' p,p implies a = b )
assume
a,b '||' p,p
; :: thesis: a = b
then
a,b // p,p
by DIRAF:def 4;
hence
a = b
by AFVECT0:def 1; :: thesis: verum