How much of a person personality do you chalk up to their zodiac sign?

You know people say Pisces this and Cancers that but really if an individual acts out a certain way how much of their personality is based on their zodiac sign and how much just has to do with their upbringing and their environment? If someone is moody or self centered or whatever characteristic you want to give them, I don't think it's safe to say they are that way because of their sign? where is the line drawn? How do you know they don't come from a family of selfish people?|||There is more to a person's behavior pattern than just their sun sign. There are most placements that go into detail to the questions you ask above. First you have to know something about the planets and what effect they have. It's a lot more than what a lot of people realize is just on the surface. You could study this stuff of years and years and not know everything!|||just the sun sign? not to o much. it's not the whole chart after all. but if it's aries or leo then i would attribute a lot to the sun sign. because the sun is quite strong in those signs. but either way, you need to look at the whole chart. and then even the whole chart can't account for 100%. as people do have free will and may have made many different choices that took them down any different paths.