Radicals ( Radical15) two strokes in Kanji;
dimensional, e.g.
left vs. right;
directional, e.g.
;
logical, e.g.
something horned;
numerological, e.g.
2;
structural, e.g.
2 strings are NOT parallel;
IFF zero Curvature surface, 2 Green Ones may begin; Also see: Monbusho level knowledge enhancement 1, idea ♯ 183, Green Ones;