Hmm, thats a good question. He did love, or at least didn't hate Mr Earnshaw...
I think he just didn't wanted to hurt Hareton. Maybe he saw himself in that younger boy (Hareton was alone, needed a family just like Heath) :)

You know as much as I HATE Heathcliff (its a recent thing lol) the thing about him was he never bothered to hide his feelings about others - he's only put on a facade twice in the book. Once for Isabella and then younger Cathy. Other than that, he made it pretty clear if you liked you or not. But I think what I did was make a common mistake - I interpret Heathcliff too simply. Either he loves or hates. But its possible for him to like too. I mean he likes Nelly - would tell her everything when he was younger, and even a few times as an adult. But could we apply the same to Hareton and Mr Earnshaw. if so why, and how?

Yeah, with Heath what you see is what you get. (i just love saying that sentence xP)
I agree with you. He wasn't afraid of showing how he felt about the others. But, like everything else about him, he took that to the extreme.

^So are you saying that because he was 'extreme' in his actions towards any of the other characters - he didn't love them?

Not exactly... he was extreme in everything he did - he was abusive, rude, a jerk LOL, and he was like that even in his feeling towards others. He didn't have limits, he said what he thought of that person even if that meant hurting someone.

^I agree. But does because he was extreme, do you think it wasn't possible for him to like anybody else? Like Nelly? Cz he there's indications he likes her then he doesn't. But just to be clear, BlackSamdals, are you saying he has extreme reactions to the people he supposedly 'like's' or 'loves' aswell?

Yes, He liked Nelly because she wasn't mean to him like everybody else... And yes he is extreme even to the people he loves - Cathy for example! Like we said in a previous forum discussion he was obsessed with her :)

I think he definitely loved Mr. Earnshaw. My memories of the book are pretty shaky, but I seem to remember him having fairly mixed feelings toward Hareton. He tries to mistreat him as a way of venting his anger at Hindley, but actually finds it difficult to dislike him. Correct me if I'm wrong.