In astrology the rules happen to be about stars and planets, but they could be about ducks and drakes for all the difference it would make. It's just a way of thinking about a problem which lets the shape of that problem begin to emerge. The more rules, the tinier the rules, the more arbitrary they are, the better. It's like throwing a handful of fine graphite dust on a piece of paper to see where the hidden indentations are. It lets you see the words that were written on the piece of paper above it that's now been taken away and hidden. The graphite's not important. It's just the means of revealing the indentations. So you see, astrology's nothing to do with astronomy. It's just to do with people thinking about people.