fof(ax_I6,axiom,(![A,B,L,P]:((point(A)&point(B)&line(L)&plane(P)&A!=B&inc_po_l(A,L)&inc_po_l(B,L)&inc_po_pl(A,P)&inc_po_pl(B,P))=>(inc_l_pl(L,P))))).
