On the off chance you're not trolling: Moriarity didn't learn to exist outside the holodeck, he was tricked. Also, he was created 100 years or so after this film takes place.
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Oh, come on! Do you have to be so immediately dismissive? This is a legitimate and informed idea that just takes a little imagination (not to mention, a sense of humour) to speculate on. Yes, it was somewhat tongue-in-cheek, but it’s not completely unworthy of discussion.
The timeline IS completely different now, after all. But who is to say in that new future reality, that Moriarity couldn’t have realized he’d been double-holodecked, gained corporeal existence by his sheer will, transcended time and space (which is certainly possible in that world, as Q and others have shown), and come back to sabotage Earth as revenge for being duped?
OK…it’s a real stretch…but jeez…it’s just an idea. Given that we’re apparently stuck with an ‘arch nemesis’…It seems a lot more compelling than the mundane ideas floating around at the moment.
IMO, Moriarity was actually one of the most frightening characters of all, given his subtly, his complete lack of fear, his incomparable intellect, and the depth of his unending and merciless
will to power…. It IS possible!
(Plus, it's not any crazier than some of the other possible ideas.)
:confused