the planets are all on paths which were determined billions of years ago.
oceans, mountains, meteors, animals, life...
With a big enough computer, one could analyze the big bang and predict what would happen, right?
Everything is a result of upbringing and innate 'how we are built'. We have free will, but the decision making process is ingrained in us, down to the random abnormalities (bonehead things we do).
so I'm a beilever in pre-determined, but we exercise free will too... it's just that an analyst with enough RAM could predict it accurately.