Positive? Zhèng〈 < refers to things. Oracle Bone Inscriptions-shaped, the symbol on the top indicates the direction and goal, and the foot on the bottom (stop) indicates walking in this direction or goal impartially. Original meaning: impartial and aboveboard.
Don't sit up straight. -"The Analects of Confucius Bitterness"
The rope is not straight. -"Lv Chunqiu Jun Shou". Note: "Straight, straight."