actually chinese astrology (and western) is really, really complicated if you go deep into it
it's the year, the month, the day, the hour wich you were born
and that all correlates with the 5 phases(elements) and the earthlybranches and celestial stems
when all is taken into consideration, you have a pretty much accurate picture of the person's personality
just like in western when you look up for the moon, the planets, elements etc
very fascinating stuff, but very hard to learn...
i'm a dog (forget all the rest =P)
and I'm cancer with moon in Aquarius (and i don't remember the rest either hahaha)