Maybe Arima was aiming for a greater purpose all the time. He took Haise under his custody to create someone stronger than himself.. someone strong enough to fulfill his objective in his stead. He could have killed Kaneki countless times.. 645 times to be exact.. but 645 times he decided not to do so. And we know that Arima isn't stupid.. that he normally does not talk with his prey.. He pushed Kaneki over the edge, he evoke his desire to survive, he fought him so that Kaneki was able to "hatch from the egg".I think his defeat finally redeems him.. I assume he chose Kaneki because he have sensed his potential during the Anteiku Raid. And maybe even sympathised whith him, because of their shared love for literature. Even thought the fight was very one-sided, Kaneki was able to scratch him nonetheless.. Arima decided to use Kaneki as his Quinque.. and now, that the Owl Quinque is destroyed (and Owl defeated), Kaneki has become the most powerfull "Quinque". Probably even the most powerfull ghoul (together with Furuta?).Arima might really have developed parental feelings for Haise.. Even though the way he trained him seemed very cruel.. The way the two of them where facing each other while none of them intending to kill the other person.. this scene was really heartbreaking somehow.I assume if Arima would have stayed alive, he would have been in Kanekis way due to his position in the CCG. I wonder what he was planning.. Maybe to defeat Furuta? Or to defeat V? To create a world where humans and ghouls can live together peacefully..? Because if he were fully convinced of the CCGs policy he would not have bet everything on a half ghoul..Arima is such an interesting character. Even after his death his true intentions are so misterious. His cold, rational and cruel behavior, that no one understands.. To me he always seemed very lonely and somehow sad.. I really liked him.. Always thinking that there is more to him that meets the eye...... I hope we can assume that Arima is the "dead Special Class"? Because loosing both would be just to cruel :(