Sometimes what I actually love to do is go to a farm and get fresh milk or watch a pig get slaughtered.

You have formal rehearsal, a lot of things you don't have in movies - which is, you have to formally rehearse. You have to know your back story, discuss it, and almost everybody onstage has to know each other's [story], so that when it comes time to actually do it, you can throw it all away. That's the way I like to - and I didn't realize until very recently - that's the way I like to prepare for movies.

I think, now, younger generations do take that for granted in a lot of ways. I don't think that takes away from the struggle of identity and what that is. But the struggle for identity is everybody's struggle. No matter what it is.

When I look at that now, all I think about is what a master [David Fincher] I was working with, and all of the things I could have watched and learned - and I didn't. And how, now, in my career, how I would love to have a ton of takes.

As Uta Hagen would say, there's the representational actor and the presentational actor. My sister [Maggie Gyllenhaal] came up to me recently after she saw this movie, Southpaw, the movie I did, and she thought there was this exploration of that type of presentation, and a bit of representation as well, if I could be totally honest, where she was deeply moved.

I don't want to be lofty when I say this, but I don't know what a success is any more. I know how we define it, but that was a moment where I went, "Wait, who am I?" You could feel the business, in particular, kind of go "He's all right, let's go over here." I started to go, "Wait, I know why I love to do this." I think I got off track in why I love to do it.

I promise that, one day, everything's going to be better for you.