positive, correct

正 is composed of 止 (stop) and a horizontal line, the line is the simplified form of 囗 (enclosure of a city). 正 is the picture of a foot walking towards a city, means conquest, but such meaning has been replaced by 征. On the other hand, 正 is also used to describe something just and correct, since in ancient China, a righteous reason is a must before conquering someone.