Obviously I'm refering to the Cylon who seems to be inside Baltars head and not the number between five and seven.

She planted the idea that she could be some sort of chip implanted into his brain that contains her "Program". Others on these boards have suggested that baltar is infact insane and six could just be a figure of his imagination.

My personal opinion is she is "Real" in some sence, we've been lead to believe that a Cylons conciousness can be downloaded from one body to another when they die. It's not beyond the realms of believability to think that six somehow download herself into Baltars brain. Bio Cylons are supposed to be identical to humans both inside and out so there shouldn't be a problem with the biology-mechanics of it (perhaps that's what to whole glowing spinal cord was all about).

No way to know untill we get more info from the show, I don't know much about psychology but it seems everything could be explained by mental instability on Baltars part just as well as if six was really there.
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