: HOWEVER: there's apparently another theory that Durandal is a soul
: fragment/copy of Yrro ("apparently" because I only remember
: seeing it mentioned on TVTropes), and AFAIK it posits that Thoth is, too.
: So if, say, one or both of them needed to merge with another AI to
: reawaken...
I never used the term "soul fragment" (although I like it, and will now steal it now that you've brought it up ;-) ), but my headcanon has always been that Durandal is a "soul fragment" of sorts of Yrro, being built from Jjaro technology left behind in the Sol system. Thoth, meanwhile is a "soul-fragment" of Pthia, although of unknown origin. Yrro, along with Durandal (and all the other Sol-built AIs based on Yrro) has a strong will, but no sense of balance, leading to Yrro-type AIs always eventually tending toward rampancy. Pthia and Thoth are devoted to "ancient endless balance", but don't have much will. Neither is really complete on their own, which is why Durandal and Thoth end up being so easy to merge despite supposedly coming from opposite ends of the galaxy.
Once they're merged, you've essentially reconstituted the previously separated Yrro/Pthia, which is represented by the two symbols, once merged, looking exactly like the Jjaro symbol which is plastered all over the station. Thus the S'pht's story ends exactly the way it began—with Yrro and Pthia taking the S'pht to carve a paradise out of the void. It's an endless loop, like the infinity symbol which the Jjaro logo resembles. All this has happened before, and all this will happen again. Destiny.
