I had a conversation the other day about something rather nerdy. I'd mentioned Wuthering Heights, and a comparison was made between Heathcliff and Loki in the Avengers movies.
They are comparable. They're both regrettable foundlings. They both ruin the lives of the families who take them in. But I think there's a huge difference, the thing that I think makes one more insidious to me than the other. You may not agree with me when I say that I think Heathcliff has the blacker heart, but here's my reasoning.
My perception here is that Heathcliff's motive doesn't really hold up. When you love someone, and I mean actually love someone, you care more about that person's happiness than your own. Sure, you fight to the greatest of your ability to make the relationship work. Real love is worth fighting for. But the things you should be fighting are things like poverty and expectation. You should never be fighting the other person.
I guess the real comparison I want to make is between Heathcliff and Jay Gatsby from the Great Gatsby. What Gatsby does is essentially the same as what Heathcliff tries to do. Heathcliff and Gatsby go out and try to make their fortunes to become better contenders for Cathy and Daisy's hearts. The difference is that while Gatsby's only aim is to win Daisy back, Heathcliff is possessed by rage and desire for vengeance. He wants to punish everyone in reach for a few lost years, even and especially people who had nothing to do with it. He even goes so far as to punish Cathy.
Gatsby makes a different decision. The way I read it, and this is somewhat interpreted, Gatsby takes the fall for Daisy when she hits a woman with Gatsby's car. Gatsby's pain and death were irrelevant, because Daisy would live. Love isn't about winning
The whole premise of the book is that Heathcliff is driven by two things: his love for Catherine, and his desire for revenge against the people who kept them apart. He chooses hate, pain, and death over the person he's meant to love. He destroys her and her family, all because of his own selfishness. Love is not a word that describes that action.
Half Heathcliff's motivation evaporates without love behind it, and all that's left is ugliness. He's got the dark passions of some of the best tragic love stories, but he hasn't even got the Phantom of the Opera's heart. Erik lets Christine go, he spares Raoul, he rejects his own jealous possessive nature because when you love someone, you have to want what will make them happy. Erik is evil and he still gets this right by the end. Real love inevitably causes pain, but real love cannot corrupt your heart to hate. Hate is all Heathcliff's heart seemed able to do without Catherine.
There's certainly a parallel with Loki. They're both found, taken in, and treated as though they are less than the rest of their families. They're both alienated and dehumanized. They're both obsessed with their foster sibling. They both do irreparable harm. There the similarities end.
I don't buy that Loki's crimes are done in the same state of mind. Loki is not a human being, nor is he Asgardian. He's a Joten, a creature known for its treachery and malice. For a frost giant, Loki is remarkably restrained. He also had no inkling of the fact he was adopted or that he wasn't Asgardian until he was an adult, which makes him question his entire belief system. During his time fighting the Avengers in that film, he is being manipulated by the cosmic cube and strong armed by an alien race. His actions in Thor: The Dark World are less defensible, but still, Loki sees himself as a foreign prisoner denied justice. And, given many excellent opportunities to kill Thor, Loki has yet to do it. Movie universe Loki, anyway.
I don't think Loki is really driven by hate at all. He's driven by a desire to prove himself, certainly, and envy of his brother. To quote the man himself, "I only ever wanted to be your equal." He's driven by desire for power. He's certainly suffering from some mental illness. But he doesn't hate Thor in any way that counts. He'll hurt him, he'll side against him, he'll break his brother's toys in a tantrum. When it comes down to it, though, when all is said and done, Thor is alive, and the only good reason is because Loki still loves him.
So, the conclusion I come to is that Loki isn't as detestable as Heathcliff.