Light and Darkness are poles of the same thing, with many degrees between them.
The musical scale is the same–starting with “C” you move upward until you reach another “C,” and so on, the differences between the two ends of the board being the same, with many degrees between the two extremes. The scale of color is the same–higher and lower vibrations being the only difference between high violet and low red. Large and Small are relative. So are Noise and Quiet; Hard and Soft follow the rule. Likewise Sharp and Dull. Positive and Negative are two poles of the same thing, with countless degrees between them.
Good and Bad are not absolute–we call one end of the scale Good and the other Bad, or one end Good and the other Evil, according to the use of the terms. A thing is “less good” than the thing higher in the scale; but that “less good” thing, in turn, is “more good” than the thing next below it–and so on, the “more or less” being regulated by the position on the scale.
So it is on the Mental Plane that. “Love and Hate” are generally regarded as being things diametrically opposed to each other; entirely different; unreconcilable. But we apply the Principle of Polarity; we find that there is no such thing as Absolute Love or Absolute Hate, as distinguished from each other. The two are merely terms applied to the two poles of the same thing. Beginning at any point of the scale we find “more love,” or “less hate,” as we ascend the scale; and “more hate” or “less love” as we descend–this being true no matter from what point, high or low, we may start. There are degrees of Love and Hate, and there is a middle point where “Like and Dislike” become so faint that it is difficult to distinguish between them. Courage and Fear come under the same rule. The Pairs of Opposites exist everywhere. Where you find one thing you find its opposite–the two poles. The Kybalion.