In your opinion, how much of our personality is genetic, and how much is shaped by environmental factors?
I believe it would be an extremely rare case, if not impossible, to meet someone whose environment had absolutely no effect on them at all throughout their lifetime.
I believe that a person becomes who they are based on every situation they've ever been placed in. We're always learning, always changing; you may be one person from birth and slowly change over time and you may have one situation change you drastically.
I'm sure there are things encoded in our brains from birth, but we always have the power to absorb, to disregard, or to overcome. When raised, we're taught basic morals (or lack thereof) and we choose to either stow them or throw them away.
And if my rambling has made any sense at all, I believe my point was that most of a person's personality is based on their environment (nurture - or lack thereof?) and that a small portion may come from heredity.
Yeah, I'm a little low on sleep. Give me a break.