Mechanical Cat Fish said:
Whereas I have to say I love you for quoting Pratchett, I would also say that, yes I've struggled with that question myself, and yes, Satan would drive to work on a steamroller made of chocolate before I'd stab my mother for no reason, but what about the infinite other options which are likely and all the options that stem from that. Just because you wouldn't do one thing it doesn't mean you would do another, and as such the idea that the constant choices we make mean our futures are in no hands but our own remains valid. So still, no, destiny doesn't exist.
But your choices, at every stage, are from a fixed range of options. Meaning that no matter how psychotically indecisive you are you have limited range of outcomes (limited being a relative term, it's a massive range of choices). There is no alternate universe where you die in another galaxy on top of a pile of slain krkk'nt foes after making love to their queen (damnit).
Some would argue that because we are who we are, there is only *one* choice we can make in every situation. Choice is a very overestimated factor, humans are creatures of habit. Lets say you don't kill your mother. You're likely to go to work to keep your job, and you're likely to do the job laid before you. So that cuts down the range of possibility (still monumental). You're likely to have the same breakfast you always do, or at least buy it from the same store... in the same-ish price range. You're likely to drive, likely to talk to friends and probably unlikely to say 'bugger all this' and just take the day off.
The fact is that because we choose one choice, it means there is
no other choice we could have chosen. Your mind doesn't weigh up and assign each option with consideration, every alternate universe of
you is still you, and will make the same choice. Even the most agonizing indecision always comes down to one choice, and provided the details are the same you'll always pick the same option.
Rocks don't change direction in midair. Things don't fall up. People react to available information and a billion other factors but the outcome is, in fact, fixed. Add in the logical impossibility of the 'many universes' idea (where does it get the energy from? does the spin of an electron split the universe? What about quantum multi-states? There's more proof and reason behind God) and we come out with humans as sort of animate matter, the graceful predictability of rocks in space.
Luckily, this doesn't stop free will. We can't look into alternate universes or observe the future. Your choices are very much
your choices and the fact that you can't make others doesn't change the fact that
you made that choice. You aren't locked into a path, because changing path is in fact part of the script your mind writes on automatic. Your choices are predetermined by you (ever known what somebody was going to say before they say it? You can get to know people) and your environment. But they're still yours.
Your choices are your own, but you can only end up in one place. The good bit is that it will be a product of your choices, not a cosmic game of chess. The bad bit is that if we ran your life again from the start, it would probably end up the same. Until we can see the future or the impossible alternate realities, it's a moot point in any case.
Long story short: You have only one choice, but it's only because you wouldn't want to do things differently.