Generally speaking, 'destiny' is not a concept I like to encounter in my science-fiction (unless it's an overt conflation of sci-fi and fantasy generic conventions, like Star Wars), because a) it is a religious, or at the very least sprititual notion, which often rings false in the setting, and b) I expect that what makes a hero in science-fiction is external--knowledge accrued, tools, etc. To generalize, the wondrous elements in sci-fi, being technology-based, are available to any who can learn to use that tech. In fantasy, you're born with whatever wondrous abilities you have--Force powers, magical aptitude, planeswalker spark, etc.--and those who aren't born with such innate skills can't attain them (again, generalizing) which creates a kind of privileged class from the get go. Both formulations can be used to create good stories, by my preference has always been for the former, which I find is more humane.
That said, I agree with casey that I'm not particularly put off with 'destiny' as it operates in Deep Space Nine, because it's not really 'destiny'. Bajorans and other may choose to interpret it that way, but there is also a rational, secular explanation for the Prophet's 'prophetic' character, which is that they exist outside of linear time. When they speak of the future, they don't do so in any kind of oracular way, but because they've actually observed it. Further, it isn't 'destiny' as this is usually conceived, because we've seen a number of times when events did not unfold the way the Prophets had originally viewed it, when Sisko and other characters have resisted the Prophets' normative schemes for linear time unfolding. Predestination sensu stricto and free will cannot coexist, but free will obviously still exists in this context, so nothing can be predestined; instead, think of it as probability: if I release a pencil in mid-air, it is not predestined to fall but is overwhelmingly probable to do so. Likewise, events need not unfold as the Prophets have foreseen them, but are likely to do so, particularly when the Prophets intervene in linear time to guarantee the results they desire. This is apparent even in recent offerings; Sisko defied the Prophets twice towards the end of the series by going to Cardassia and marrying Kassidy; in Fearful Symmetry, Sisko attends a gathering of his counterparts across a number of universes, which indicates the high probability of Sisko(s) becoming Emissary, but one Sisko (the MU Sisko) is absent entirely, indicating that there is no ironclad notion of fate at work.
Fictitiously yours, Trent Roman
