James Cameron is sharing one of his favorite moments from “Barbie” with Greta Gerwig, the film’s director and co-writer. It’s America Ferrera’s showstopping monologue, the one that had audiences breaking into applause as her character slams the impossible demands society imposes on women to be successful in ways that don’t threaten men. “You basically sum up thousands of years of the female dilemma in one minute,” Cameron says. “I don’t think it’s ever been done as succinctly and hit the mark so perfectly.”

Cameron delivers that verdict via Zoom from New Zealand, where he’s making the next “Avatar” film. Gerwig is half a world away in New York, but despite the geographic distance, the two have an easy rapport. Perhaps it’s because they share the novel experience of having directed billion-dollar-grossing, culturally defining blockbusters. Their discussion is being taped, which has Gerwig peppering the camera crew with questions about lighting and angles. “You can take the director off the set …” Cameron says with a laugh.

JAMES CAMERON: Did people see how risky “Barbie” was?

GRETA GERWIG: When you look at it in retrospect, everybody thinks, “Well, of course that was going to work.” But at the time, no one knew it was going to work. Because time only moves in one direction, things seem inevitable that were anything but inevitable.

CAMERON: What led you to commit a couple of years of your life to “Barbie”? You must have seen some out-of-focus version of that film in your mind and said, “I can do this.” At some point, you also say, “I’m the right one to do this.” You must have said, “I, Greta Gerwig, am the right person to go make the movie about Barbie, the great feminist icon, capitalist symbol.”

GERWIG: I tend to back into things. Everything I’ve made, I’ve started by saying, “Well, I’ll just write it.” Even going back to “Lady Bird,” I thought, “Well, I’ll write this, and then I’ll give it to someone else to direct.” I couldn’t quite conceive of doing the whole thing. With “Barbie,” I loved Margot Robbie as an actor, and she’s done great work as a producer. She came to me and said, “I have this IP. You can do whatever you want with it.” I said, “I’d like to write it with Noah [Baumbach],” because we hadn’t written together for a while. We don’t do outlines or treatments, we just write a movie. We start with ideas and scenes. The story emerges from that. So we said, “Leave us alone and then we’ll give you a script.” It felt like a degree of self-protection to say, “Well, I’d like to direct this movie, [but] you’ll never make it.”

CAMERON: It’s like, “If you’re dumb enough to hire me, then we’ll go to the next step.”

GERWIG: Initially, the budget wasn’t enough, and I said, “Well, listen. It’s ‘Barbie.’ It needs a big canvas.” I feel like with each movie, I’m still learning, I’m figuring out how to do things differently than I’ve done before. At some point I think I said on the phone to someone, “I’m going to have to be a better director than I’ve been in order to do this.”

CAMERON: It’s healthy to feel that hunger for improving your craft indefinitely. I always want to know, “Who’s doing what? What’s the new tech? What are the new ideas?”

GERWIG: So many of your films have pushed technology forward. They require more of movies than has yet been available ? “Abyss,” “Terminator 2” and now with “Avatar.” Do you have a sense, while you’re writing, “There’s no way to do this yet. I’m going to have to invent it”?

CAMERON: I’ve had imagery in my mind since I was a kid that there was no way to do. It’s only in really the last decade that we’re at a point where pretty much anything I can imagine is now doable. I like getting in over my head. I always feel I’m best when I’m pressed into a corner.

GERWIG: I tend to trap myself and then think, “Oh, how am I going to get out of this?” Having that sense of “I’ve got to build my parachute on the way down.” Are you adventurous? Do you skydive in your life?

CAMERON: More so in the past. I used to go out and do all the gonzo stuff. I’ve always loved riding motorcycles. But now I find that there’s enough risk to be managed doing an ocean expedition or something like that. What about you? Are you jumping out of airplanes?

GERWIG: Not explicitly so, in terms of jumping out of airplanes. I like being swept up in things that I don’t know how they’ll end, like buying plane tickets without a return ticket. Sort of like, “I don’t know how this will unfold, but yet I’m here.”

CAMERON: As a director coming from an acting background, are you channeling the directors who did you the most good or reacting against the ones who did you the least good?

GERWIG: I’m trying to channel the directors that did me the most good. I’ve had moments where I’ve tried to imitate something I’ve seen, and it’s just a disaster. I have to be myself, otherwise the actors can smell it. On “Lady Bird,” [the studio] wanted a director picture, and they were like, “Do you have any pictures of you pointing?” [Because] it looks directorial. Then I thought, “Oh, gosh. Should I point more? Do I point enough?” Then I was like, “You do it how you do it.”

CAMERON: Talk about Ryan Gosling. He was incredibly brave as Ken.

GERWIG: Noah and I wrote it for Ryan. I’d never met him, but I loved him as an actor. I thought he was always very funny, but he was funny from a place of total sincerity. He came to rehearsals, and I saw him and Margot, and I had a moment where I looked at the two of them acting together and thought, “I want to watch this movie.”

CAMERON: If you can’t cry at your own movie, how do you expect millions of people to cry? You have to be a movie fan first when you’re looking at your own stuff. If you get too intellectual, you’re going to come up with something that may be quite artistic, but it won’t be heartfelt. The triumph of “Barbie” is how heartfelt it is. Talk to me about the reaction, your personal journey, as the film was accepted, as it was successful. What was that like?

GERWIG: It came out on July 21. Then I spent all of August being a carpool mom. I was taking my kid to camp every day, and I shut it down. I have two boys and a stepson. I have my own wonderful Mojo Dojo Casa House. In a way, I was in a bubble. The thing that makes me excited is that I hope I get to make a lot of different movies, bigger movies, smaller movies. It’s the feeling that I’ll be able to have access to the size of the canvas I need.

CAMERON: When you need the size, people will trust you with it because you used that palette correctly?

GERWIG: At least they will one more time. There’s a certain amount of creative freedom that I feel like it unlocks. I can paint with more colors.

CAMERON: I mean, I wouldn’t have been allowed to make “Titanic” if I hadn’t had some successes on films in completely different genres. “True Lies” was a big film for its time. “Terminator 2” was the highest-costing film in its time. Success on those led to me getting the resources I needed to make “Titanic.” Now, that said, there was a moment on “Titanic” where we all thought we were doomed and it was going to be a big smoking crater. It connected. So then I got trusted to make “Avatar,” which was also quite ambitious. So I agree with that. In principle, you do earn the right to at least be heard.

GERWIG: I collect stories, obviously, of directors ? you, Alfonso Cuaron, Steven Spielberg, all these people.

CAMERON: I deny everything!

GERWIG: But I look at these stories and I feel like they stuck to their guns. I said to my producer, David Heyman, “You should start circulating more stories about directors who compromise and it works out. The only stories I hear are of directors who say, ‘No, we’re going to do it this way.’”

CAMERON: Sometimes compromises lead to something that actually works. When we were making “True Lies,” we had this elaborate setpiece that was going to take place up in these snowy mountains. There was skiing and a crashed helicopter. [Arnold Schwarzenegger] winds up skiing a helicopter on its skids down the mountain ? a big James Bond sequence. We shot one night in the mountains. I had this horrific image that we were going to be there for three weeks. We were already behind schedule. At that point, I knew we just wouldn’t hit our release date if we stayed there. I got the crew together in the hotel the next morning. I said, “We’re going to finish the scene tonight. The helicopter’s out, this is out, that’s out. He shoots two guys, jumps in the van, they drive away.” We finished it in one night.

GERWIG: That’s a good compromise story.

CAMERON: The rule should be “If it’s brilliant by mistake, take credit.”

Variety Directors on Directors presented by “American Fiction.”