Confirmastion: Their character:

(1) If there is light,

(1-1) There is something, we can proof.

(1-2) There is something, we cannot proof.

(2) If there is shade, 

(2-1) We can proof (1-2).

(2-2) We cannot proof (1-1).

The above is living sector question, which is famous as one of proofing technics in chemistry and physics.

Someone misunderstand the above.

1. If there is light, there is the shade there.

D: "Confirmed."

The shade:

Nintendo:

*word expression

1-1.living sector question

1-2.division

1-3.bipolar( in physics )