Fate? No, i don't believe seriously in such a thing. One could argue that it was everyone's fate all along to become what they are, but then again, it could all just be random chance and/or determined by the environment. In any case though, if fate does exist, it's an inarguable and individual constant for every being in the universe which cannot be known until it has happened, and thus, in my mind, is not worth thinking about.
Free will? This is where things get interesting, because psychology has proven that environment has a HUGE impact on how we behave, or at least what we feel like we should behave, along with countless other subconscious things. Phobias, for example, can be instilled in people from a very early age (by connecting something with an upsetting event), and will likely stick for the rest of their lives.
Also, ever heard of Pavlov's dog? That phenomenon is not restricted to dogs and other beings of lesser intelligence than humans. I can guarantee you that if you were to be served food immediately after a certain bell got rung over, say, a few years, hearing that bell again, even years later, will INSTANTLY make you think of food and the good ol' times, and possibly even instill great nostalgia.
So, in a way, we don't have free will. Subconscious things are just that; below your consciousness. Your conscious acts are strongly affected by your subconscious; for instance, you might say "i'm not the kind of person who'd strike someone down at random", and that might very well be true, and you might very well have a little voice in your head saying that it's completely wrong to do that, but you CAN still do it on a whim if you ignore those feelings. In that way, we do have free will, but it's strongly shaped by your upbringing.
IN THEORY (since i do not advocate such a practice), you could almost certainly take an infant born by the pairing of the two most vicious serial killers on the planet, put said infant in care under a regular loving family, and get a perfectly ordinary child as a result. However, if said infant were to be raised by said serial killer parents without them going clean regular parent mode, it's very likely that the child will grow up to become a criminal. When it comes to personality, genetics mean surprisingly little.
You know all those things you think and feel are right and wrong? That's probably because you were taught so by people who were taught to behave how they are. Infants have JUST been ejected out of their little bubble and into the cold outer world, but they have NO idea how to behave in this world, a bit like an adult being shoehorned into a completely different culture, except with nothing in the luggage. As with animals, they will shape their behaviour according to what gives them the most goodness and least badness, and in the end, our personalities can damn near be summarized as a LONG list of things that have brought us good's and bad's. Touch thorn bush = Get hurt = DON'T DO. Eat food = Taste good and remove hunger = DO IT MORE. But of course, that doesn't account for everything, and i'm reasonably sure we don't know the rest of it.
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