Naruto Shippuden Episode 35

[Uberbaka]

Sorry Kraco, but that is wrong. Several types of Schitzophrenia include symptoms of lacking empathy and emotions and it can come from other kinds of psychological or physical stress/injury. The exact term for it is called Alexithymia.

(The lack of empathy part would be the one that makes a person unable to know how anything would affect anyone else and what faces to make in any given situation)

Lack of emotions is real, imagining how it "feels" is probably close to impossible for normal people, but it happens.

Take autistic people as a different example.. People with autism have social impairments and often lack the intuition about others that many people take for granted, these which you say you have to be an idiot to not understand. (No, I'm not saying he's autistic... Just an example of how the brain -can- work)
</psychology lecture>

[Kraco]

Fine, you might be right, and I'm certainly no expert at psychology... But I still can't personally imagine it. And from my point of view Sai certainly doesn't appear to be a person without emotions, but a person with supressed emotions and either a somewhat twisted personality or a highly calculative nature (goes along with suppressed emotions) with a as of yet unrevealed plan.