This happens to me all the time or used to. I've been busy lately so my dreams have been low in numbers

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Anyway, It was mentioned in Big Fish when I watched it a few days ago, which got me interested again.
My theory consisted of the subconscious being able to put together a scenario of what could happen "in the future". Thus, subconsciously you will probably end up doing it without notice.
Then I remember reading Slaughterhouse five from Kurt Vonnegut. Somewhere in the beginning theres mention of a friend who says he was abducted, and the abductors could see 4 dimensions instead of 3. They also looked at time as moments whenever; and that we humans can only see forward and what has happened is the past. They see it as present with no future or past, just observers of a cluster of moments.
So it brings a far off idea that based on whats already happened, many scenarios could be presented to happen in the future, but inevitably those currents of events could have led to that and only that occurrence.
Hm.. maybe that didn't make any sense. I need my cup of coffee!