let X be set ; Total X is strongly_connected
let x, y be object ; RELAT_2:def 7,RELAT_2:def 15 ( not x in field (Total X) or not y in field (Total X) or [x,y] in Total X or [y,x] in Total X )
assume
( x in field (Total X) & y in field (Total X) )
; ( [x,y] in Total X or [y,x] in Total X )
then
( x in X & y in X )
by ORDERS_1:12;
then
[x,y] in [:X,X:]
by ZFMISC_1:87;
hence
( [x,y] in Total X or [y,x] in Total X )
by EQREL_1:def 1; verum