let R be Ring; :: thesis: for V being RightMod of R
for W being Submodule of V holds 0. V in W
let V be RightMod of R; :: thesis: for W being Submodule of V holds 0. V in W
let W be Submodule of V; :: thesis: 0. V in W
( 0. W in W & 0. V = 0. W ) by Def2, RLVECT_1:3;
hence 0. V in W ; :: thesis: verum