Probably spoilers.
Merging is the negative in most cases, the pathological option. Vincent with monsters and chaos. Cloud, mentally, with Zack. Aerith with Red XIII, at least that was the intention. Sephiroth with Jenova. The reactor prisoners with mako. All of these are, in some measure, uncontrolled, and result in psychosis.
The other end of the spectrum seems to be the gaia process--the Lifestream. This version of unity allows for individual integrity in its time, and for the individual to exist for a full span before returning to the collective.
DoC implies that the Lifestream itself is migratory in the sense that it reincarnates. That, when the planet has reached the end of it's span and senesces, chaos returns all form to energy and omega encapsulates all life in a migratory form for the journey to another body/planet/incarnation. Alternate possibility, the sum of the Planet's life/experience returns to the Universe at large (universal lifestream?) in the same way a terrestrial life returns to the planetary lifestream. Confirmed. Note terminology: life/stream/ and /sea/ or /ocean/ of stars, and the rain/spring imagery associated with Aerith in AC. Rain into river. River into ocean.
And, again, the actions of the villains are focused on bringing about that end before its natural time.
Theme: evil = natural processes accelerated or forced rather than allowed to develop in their own time.
BC's Fuhito and his intention to use the zirconiade summons to much the same ends as chaos falls into this theme, but on a different level--the level of human action on which Meteor and Holy both exist. The existence of materia, as opposed to WEAPONs, that summon the death of all life, the destruction of the world/body and the cleansing of threat implies that humans, as the intelligence of the gaia process, are entrusted with or perhaps simply evolve the ability to affect the process according to their own judgement of what is necessary. As such, it may be the Fuhito is not acting out of time, but rather is acting in his part as a human/thinking element of gaia.
Of course, resistance to his goals by other humans must, equally, be part of that process of intelligent judgement. I think the actions centering around the summons cannot be said to be out of time. Rather, they are their own part of the natural process of humans regulating /themselves/.
ETA: Okay, so either Shinra was part of the group that became the Cetra after migration to the Planet, or the Cetra were indigenous and physiologically identical humans somehow /coincidentally/ evolved in parallel on multiple worlds /and/ Shinra was part of an additional colonial wave, or there were multiple waves of human settlers to the Planet. Neither of the latter two fit at all well with the implication that all humans on the Planet derive/decended from the Cetra group.
Occam's razor suggests that the Cetra lifestyle was generated among the settlers after settlement, possibly based on pre-existing ethnic tendencies, and that the in-game references to migratory life apply to their evolved patterns on the Planet.
ETA2: Hojo spouts off, in MWTtP, about how alien life/substance becomes part of Planetary life, unbeknownst.
The G substance is variously described as contaminated mako and 'stagnation of the lifestream'. This suggests that it (and the birthplace of chaos in general) is the accretion of impurities that cannot be circulated within the life-cycle of the planet. Things that are incompatible with the continuing cycle and are expelled/encapsulated in this way. Presumably that is the nature of chaos' evolution; when the amount of unassimilable impurities reaches critical, then clearly the system is can no longer maintain itself and is dying and it's time for the last act.
What remains to be seen is whether or not Jenova will be this sort of thing or an e. coli sort of thing. Will she be rejected from the system as incompatible, in some manner of final confrontation? Or will she be /absorbed/ into the system and the system continue with an infusion of new substance (dna?)?
If the former, then Genesis and Sephiroth are both competing expressions of substances the planet ultimately cannot assimilate. If the latter, however... well that could get interesting. That would place Sephiroth almost on the 'good guys' side, against Genesis.
Merging is the negative in most cases, the pathological option. Vincent with monsters and chaos. Cloud, mentally, with Zack. Aerith with Red XIII, at least that was the intention. Sephiroth with Jenova. The reactor prisoners with mako. All of these are, in some measure, uncontrolled, and result in psychosis.
The other end of the spectrum seems to be the gaia process--the Lifestream. This version of unity allows for individual integrity in its time, and for the individual to exist for a full span before returning to the collective.
DoC implies that the Lifestream itself is migratory in the sense that it reincarnates. That, when the planet has reached the end of it's span and senesces, chaos returns all form to energy and omega encapsulates all life in a migratory form for the journey to another body/planet/incarnation. Alternate possibility, the sum of the Planet's life/experience returns to the Universe at large (universal lifestream?) in the same way a terrestrial life returns to the planetary lifestream. Confirmed. Note terminology: life/stream/ and /sea/ or /ocean/ of stars, and the rain/spring imagery associated with Aerith in AC. Rain into river. River into ocean.
And, again, the actions of the villains are focused on bringing about that end before its natural time.
Theme: evil = natural processes accelerated or forced rather than allowed to develop in their own time.
BC's Fuhito and his intention to use the zirconiade summons to much the same ends as chaos falls into this theme, but on a different level--the level of human action on which Meteor and Holy both exist. The existence of materia, as opposed to WEAPONs, that summon the death of all life, the destruction of the world/body and the cleansing of threat implies that humans, as the intelligence of the gaia process, are entrusted with or perhaps simply evolve the ability to affect the process according to their own judgement of what is necessary. As such, it may be the Fuhito is not acting out of time, but rather is acting in his part as a human/thinking element of gaia.
Of course, resistance to his goals by other humans must, equally, be part of that process of intelligent judgement. I think the actions centering around the summons cannot be said to be out of time. Rather, they are their own part of the natural process of humans regulating /themselves/.
ETA: Okay, so either Shinra was part of the group that became the Cetra after migration to the Planet, or the Cetra were indigenous and physiologically identical humans somehow /coincidentally/ evolved in parallel on multiple worlds /and/ Shinra was part of an additional colonial wave, or there were multiple waves of human settlers to the Planet. Neither of the latter two fit at all well with the implication that all humans on the Planet derive/decended from the Cetra group.
Occam's razor suggests that the Cetra lifestyle was generated among the settlers after settlement, possibly based on pre-existing ethnic tendencies, and that the in-game references to migratory life apply to their evolved patterns on the Planet.
ETA2: Hojo spouts off, in MWTtP, about how alien life/substance becomes part of Planetary life, unbeknownst.
The G substance is variously described as contaminated mako and 'stagnation of the lifestream'. This suggests that it (and the birthplace of chaos in general) is the accretion of impurities that cannot be circulated within the life-cycle of the planet. Things that are incompatible with the continuing cycle and are expelled/encapsulated in this way. Presumably that is the nature of chaos' evolution; when the amount of unassimilable impurities reaches critical, then clearly the system is can no longer maintain itself and is dying and it's time for the last act.
What remains to be seen is whether or not Jenova will be this sort of thing or an e. coli sort of thing. Will she be rejected from the system as incompatible, in some manner of final confrontation? Or will she be /absorbed/ into the system and the system continue with an infusion of new substance (dna?)?
If the former, then Genesis and Sephiroth are both competing expressions of substances the planet ultimately cannot assimilate. If the latter, however... well that could get interesting. That would place Sephiroth almost on the 'good guys' side, against Genesis.