If I understand correctly, Eben sees empathy and empathic responses as one way of distinguishing between criminal/antisocial and social behavior. The ready distinction seems to be between those who feel for and can imagine the experiences of others, leading them to treat others with respect, and those who for whatever reason can't imagine the experiences of others, and so think only of their own interests and desires. But it's not always so clear: Eben points to the case of the empathic individual who nonetheless behaves antisocially, and the complex system of internal justifications this creates. Probably most people who commit crimes fall into this category.

You say a lot here, so I will only comment on the multiple personalities issue. I do not believe Eben was saying we should strive towards cohesion. I don't even think cohesion is possible. The goal is rather one of self-awareness. For example, since Eben mentioned this phenomenon, I did further reading on the topic and began to try to pay better attention to myself as I interacted with others, waiting to see if I could decipher different personalities emerging in different contexts with different people. I personally did notice changes-- but I won't go into them here. The next step would be to understand whyyy this or that personality was created or why it emerges in particular contexts. The result is learning how to better understand and then control oneself on a deeper level-- that is, to learn to exist with multiple personalities and use them to your advantage.