Speculah:Human Soul and Magic
An anonymous user posted the following theory in thread #27:
- Here's what I think:
- A human soul is actually capable of doing abnormal stuff like shitting rifles. at all times. You can't do it because it has a limiter, just like your body has a limiter that prevents you from using it's full strength in order to avoid harming youself.
- Once a girl makes a contract with kyubey or whatever (do we even know for sure there are more contractor animals around?), her soul is like on steroids and the limiter disappears.
- However, using magic would damage the soul (for example, it produces some dark energy, I mean come on it's basically witchcraft no matter how you look at it). This is why soul gems are needed - the damage is redirected onto the soul gem and it slowly dims, corrupts instead of the girl's soul. (this part has been debunked in Episode 6, as Soul Gems are revealed to actually hold materialized souls inside)
- Once a soul gem is completely black it no longer can absorb corruption and using magic begins to hurt the soul, turning her into a witch. (this part has been partly debunked in Episode 6 - see above) (this part has been partly proven in Episode 8 as completely black Soul Gems indeed turn to Grief Seeds and make Puella Magi turn to witches)
- However, it will still absorb corruption if you "force" it to, and that's what they do to transfer it off their own gems onto the "grief seeds", which are actually completely corrupt soul gems. (this part has been partly proven in Episode 8 - see above)
- There. the only inconsistency is the "grief seed cannot absorb corruption from your soul, but you can still transfer it from another soul gem"...
- This could be because at this point, a witch perhaps can absorb corruption to become even stronger
Using magic and cleansing corruption without a soul gem
It might be possible for a normal human soul to heal corruption over time. A natural magic user could either descend into corruption-induced madness or gradually cleanse their soul depending on their purity of heart, personality, good/evil deeds, or extent of magic use. Soul gems trap the corruption, causing it to build up with no outlet.
A natural, uncontracted magical girl could defeat witches or even absorb corruption from soul gems and seeds as long as she rests and heals enough to avoid being overcome with corruption. This means she could gradually remove all the corruption from the system.
Magical girls and witches would hail her as their savior, but Kyubey would never see a grief seed again. Kyubey is obsessed with Madoka because, given the right training, she could become a natural magical girl and eliminate Kyubey's food supply.
Observations and speculations based on later episodes
Magic is only necessary to enter the witch's barrier. There is no need use magic to actually defeat the witch. As Homura proves with her guns and bombs, usual human technology is no less effective or even better than magic, even enhanced baseball bat can help against some minions. However without turning into a "zombie" it would be very hard to survive for long enough.
In fact it seems that most of the grief is generated by magical girl herself, not by her fights with witches. However witches spread their surplus grief to the other people while magical girls can only transfer their grief to a clean grief seed until it fills up and revives. It should be possible for magical girl to do same thing and transfer corruption from her soul gem to the other people, thus maintaining indefinite life.
Turning witch back into magical girl
A grief seed is basically the same soul gem just filled with grief, even the personality is still same - just completely repressed by enormous pain. Cleansing a grief seed could theoretically turn a witch back into a magical girl.
During the fight scenes, the magical girl absorbs grief from witch which makes her clean, then later sends it back. The timeline in which Madoka defeats Walpurgis easily without physical harm but turns into witch immediately with no reason seems to prove that part - she collects more grief than her capacity.
If the original body was somewhere around at that time, the grief seed could take back its control. But since body is not available it remains helpless until refilled with grief again and turns back into the witch in the same way like magical girl.
Notes about corruption
It it worth mentioning that it is wrong to talk about corruption of soul. Magical girl turns into a witch not because she becomes corrupt (evil,selfish, etc), but once she can't deal with her pain (grief). Magical girls can be far from perfect in all possible ways, but that does not do any harm no matter how evil they become, but once they can't deal with pain anymore, they fall into depression and become witches. Sayaka retained enormous power while fighting witch with mad joy, but collapsed once that madness dissipated and her soul gem started to darken immediately. Homura seems to not even need to cleanse her soul gem. It looks like she is just leaving grief seeds as she walks away from exploding witches. Other girls also turn into witches shortly after the fight, but never during the fight itself.