所以

Conjunction

 * 1) therefore; so; consequently

Pronoun

 * 1)  the means literally, "what one uses" by which; how
 * 2)  the manner in which; how
 * 3)  the reason why; why
 * 1)  the manner in which; how
 * 2)  the reason why; why
 * 1)  the reason why; why

Noun

 * 1)  proper behaviour; manners

Etymology
Shift from →  →. See. The kanji are.

Noun

 * 1) reason, grounds