Two halves brain mixed in together and id

[R_1]

Let's suppose it is possible to cut brains in halves, and mix them with the other halves, and somehow the affected lives. A mad scientist decide to attempt to do this and successfully did. What happens to the id of these people? Do they become two split being? Do consciousness become one soonly or will there be split personality for each side of the brain. 

[RoseGoesToYale]

Well, it's certainly true that a human can function with only half a brain. As for putting two together... I think it would be hard to speculate since it's never been attempted. The two halves would need to be able to communicate with each other by forming a connected net of neurons, so I highly doubt you'd see an immediate personality change even if it were possible. Over time maybe? The body would need to also not reject the foreign hemisphere.

 

I also highly doubt it would ever be attempted (but who knows) due to the existential and ethical questions it raises. You're literally messing with the human computer... imagine people getting murdered or kidnapped to have their memories or abilities transplanted into another body.

[Pandark]

Split brain surgery was done on epileptics in the past. In case of a seizure, they could remain conscious as one of the brain halves remained unaffected. Severing the connections between both hemispheres is permanent, though. It also has some nasty side effects. I don't think it'll be possible to reattach two brain halves any time soon. Once it is possible, establishing proper communication between the halves will require extensive training, e.g. even more so than for a limb transplant. Hypothetically: after a proper amount of training the two halves will act as a single personality.

[Karst]

I really doubt that what you're hypothesizing would ever be possible, so I suspect it's a moot point.