To kick things off to anyone who wants a topic to discuss, I hold the belief that one's future does not (and in fact) can not change. A type of predetermination if you will (without anyone that predetermines it of course).
My belief goes as follows
Any choice you make, you have already made. While you technically have not chronologically made the choice yet, the outcome will remain the same as if you have already made the decision.
Some believe that as you go through life, your future is constantly changing based on the choices you make; I.E: If I decide to go to become a dentist, My future is to become a dentist. If I then change my mind and want to become an artist, my future changes according to my respective decisions. I, however, believe that while you may make the decision to become a dentist, it was always in your future to decide to become a dentist. Then should you decide to become an artist, your future does not change because you were never going to become a dentist, you were always going to first decide to become a dentist and then later change your decision and become an artist. So while your decisions and desired life outcome changed, you future stayed the same.
To explain, try viewing life like a walk along a very foggy path. Every fork in the path represents a decision you make in life. At the beginning of the path, you have not made many choices yet and the path is very uncertain. However, as you walk along the path (go through life) you make more and more choices until you reach the end of the path (death). Having reflected on the route that you took, it can be said that from the very beginning of your travels, each and every time you made a decision, you were always going to make that decision. It matters not that you could have made a left instead of a right because you were never going to make a left in the first place.
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Edit: When I say it was always in your future to decide to become a dentist, I'm saying the decision you make was always in your future; not your final occupation. So while yes you were always going to decide to become a dentist, that does not necessarily mean that it is in your future to become a dentist.