Lionheart
Solid Ocelot
i think that Dante and Vergil each had their own reaction to their mothers death. revenge was Dante's reaction, Vergil's was to seek power. it's not shallow, looking into why the twins each reacted the way they did is an opportunity to figure out a lot about them (or at least create interesting theories).
huh? how would Dante know if Vergil had an answer or not before asking. this entire debate proves that the default assumption is that someone would have a rational motive for seeking power.
i am not saying their is no answer just because Vergil didn't provide one. i am saying that the entirety of his behavior suggests to me that his fathers power is something he desperately feels that he needs just to feel safe or to even begin to attempt to be content with his life. Vergil already failed to protect his mother that seems like enough to motivate his actions including that speech of his.
Dante was trying to get an answer out of him. He could've outright said what he thought Vergil was thinking, but maybe he wasn't sure, and maybe he didn't want to say it out loud. Besides, it's a vehicle to make the story more interesting. Simply telling the viewer/player what Vergil's intent is leaves nothing to the imagination. I'm saying he suspected Vergil had a motive to gain power, but that he wasn't sure what that motive was. That, or the player is intentionally left guessing.
Just to feel safe? What are you talking about? He was the strongest demon aside from Mundus, together with Dante. He tried to emulate Sparda, that much was clear. In order to emulate Sparda, he would have to rule over either the human world or the demon world, and perhaps preserve Sparda's legacy (by having a child). As he didn't care for humans much and seemed to hate demons (like Dante), I would assume he'd close the hell gate so that nobody else will lose their mother and father like he did.
After he asks Vergil what he needs that power for, he even says 'no matter how hard you try, you'll never be like father'.