set M = the carrier of V;
for u being object st u in the carrier of V holds
u in the carrier of V
;
then reconsider M = the carrier of V as Subset of V by TARSKI:def 3;
reconsider M = M as non empty Subset of V ;
take
M
; ( M is add-closed & M is multi-closed )
thus
( M is add-closed & M is multi-closed )
; verum