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 ;
hence 0. V in W by Def2; :: thesis: verum