I think because it is made of a compass and a square that it symbolizes measurement and movement. The G in the middle is probably Gnosis (knowledge) and sometimes the G is replaced by an eye which could symbolize awareness... Gnosis and awareness go hand in hand so the eye and the G probably symbolize the same thing. The compass and square encircle the eye or G... this to mean symbolizes awareness through measurement and movement. Everything we do is movement and everything we perceive is measurement. What do you think the square and compass symbolize?