let L be 1_Lattice; :: thesis: Top L is_a_unity_wrt the L_meet of L
now :: thesis: for u being Element of L holds the L_meet of L . ((Top L),u) = u
let u be Element of L; :: thesis: the L_meet of L . ((Top L),u) = u
thus the L_meet of L . ((Top L),u) = (Top L) "/\" u
.= u ; :: thesis: verum
end;
hence Top L is_a_unity_wrt the L_meet of L by BINOP_1:4; :: thesis: verum