(I've touched upon this in a few threads post "The Constant", but I'd like to place it in theory mould and attempt to build upon it over time.)
The Constant may have given us a new way of looking at 'destiny' and it's implications. My understanding is that if your concious time-travels to the past and then back to the present day, your conscious at each point in time will be given 'new memory' - things that you may not have done originally, but which have overwritten what you remember doing. Importantly you cannot change the future, but I believe that you can adjust your memories, mind-set and perception. This was seen most recently when Faraday's journal suddenly updated with a new notation from past-Faraday, after Desmond had time-travelled back to 1996 to visit him. Present-day Faraday didn't remember writing this journal entry because it was a "new memory" - one which slightly altered his previous actions (but not enough to change his path and even if it was the Universe would have course corrected where necessary).
So what about destiny? Well apart from the 'new memories' that time-travel can give people, I believe that there are things time-travel is able to adjust which we can't remember in present day form. This may be because the Universe has eradicated a paradox by causing us to forget (as possibly seen with Desmond and Faraday's various memory issues) or because the person who time-travelled into our lives has either died or not yet found their 'constant' in their original time strand.
This loss or overwritten memory is often cushioned by a sense of something..a vague recollection or 'impression' of something within you. This can be described as sensations, emotions, innate beliefs and powerful feelings that we are 'supposed' to do something great or special or different from our current course. I believe that this is where the feeling of 'destiny' comes from (in terms of how the creators of Lost are presenting the show) - a forgotten action or knowledge which has been un-remembered or not yet realised in ones 'current' perception of time.
Could this premise therefore explain Desmond's seeming 'knowledge' that Jack healed Sarah, or his optimising about going on the race around the world?
Could this also explain John Locke's sheer belief that it was his 'destiny' to go on that Walkabout tour?
Could this help explain why Jack seemed to know that it was his 'purpose' to fix Sarah (which consequently led him to the island)?
Could this further explain why Faraday was crying in his opening flashback sequence?
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Are we now looking at a new explanation for the phemenom of 'destiny' with it's potential relationship to time (or time travel)?
I think an important
distinction to make is the one between destiny and fate:
"Modern usage defines fate as a power or agency that predetermines and orders the course of events. Fate defines events as ordered or "inevitable". Fate is used in regard to the finality of events as they have worked themselves out; and that same sense of finality, projected into the future to become the inevitability of events as they will work themselves out, is Destiny. Fate is an outcome determined by an outside agency acting upon a person or entity; but with destiny the entity is participating in achieving an
outcome that is directly related to itself. participation happens willfully."
With this in mind, I believe that in Lost-terms fate is the Universe (as coroborated by Mrs Hawking) and destiny is our choice (freewill) in-between the stepping-stones of fate.
Therefore, as Faraday said and as Charlie's death confirmed, the future cannot be changed. But I believe that if the conscious is able to travel back in time, then it can unlock a sense of destiny, of purpose of vague knowing and deep belief. It is this which can allow us to correct small mistakes, to do things better, to try harder to be better. If such action causes ones path to change, then fate may course correct and delete memory, but the 'impression' of past experience still exists.
To understand this theory best, I think it's worth noting that i don't consider time to have a beginning or end - time has no past and no future, time is something which is happening all at once - this is how time-travelling is able to give us a sense of destiny, because otherwise how would we know which moment in time is which - how would we know whether 'now' is the first 'now'..or the 10th 'now' or the 300th 'now' or the 100,000 'now'? Time must be happening all at the same time in order for us to feel the sense of destiny, to feel the innate sense of purpose. C'mon, we've all felt it..where do you think it comes from? Perhaps you or someone you know has time-travelled into your past (I say 'past' even though I believe time happens all at once, simply because it's easier to explain time in terms of past, future, present)?
The hopeful amongst us will say: "It's my destiny.."
The Universe will argue: "No, It's your fate"
..Others will simply say: "See you in another life!"
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