EXCLUSIVE: Hollywood Icons Norman Lear, Jane Fonda and Lily Tomlin on Aging and Opting Out of Retirement

This video is unavailable because we were unable to load a message from our sponsors.

If you are using ad-blocking software, please disable it and reload the page.

Age ain’t nothing but a number… and maybe, it’s not even that.

At nearly 95, legendary producer Norman Lear has added a new title to his resume: podcaster. Lear launched his new show, All of the Above, earlier this month on PodcastOne, and ET was lucky enough to visit the studio for his latest taping, featuring guests Lily Tomlin and Jane Fonda.

“I was excited to be on his show,” Tomlin tells ET. “I thought he would think twice about having us on.”

“I’m always happy to be in his proximity,” Fonda says. “But my first thought was, like he doesn't have enough to do?! Now he's also doing a podcast?”

WATCH: Hilarious Grace & Frankie Bloopers!

Something similar could be said about Fonda and Tomlin, who, at 79 and 77 respectively, are in the middle of filming the fourth season of their hit Netflix series, Grace & Frankie. All three stars are defying cultural expectations when it comes to aging, each admitting they have no plans to retire.

“The cultural expectation is all wrong about aging,” Lear shares. “It's all about pains and aches, and isn't enough about expectations and tomorrows, and excitement for this and for that and the other thing. It's not about [being] alive. It's about dying.”

“They say, 'You're over the hill,’” Fonda adds. “What they don't realize is, when you're outside of oldness looking in, it's scary. But once you're inside oldness, it's not scary anymore, 'cause you realize that over the hill, there's all those other hills. And a lot of beautiful meadows and things.”

“We're climbing the hill!” Lear chimes in.

MORE: 9 Life Lessons Learned on Norman Lear’s One Day at a Time

“That's right,” Fonda continues. “The two things that keep you young, no matter what's happened to your body, is you keep climbing, keep moving. Use it or lose it, it's an absolute truism. And the other thing is, maintaining a sense of humor and being curious about life.”

That curiosity includes a vested interest in social causes, which Fonda has been associated with for decades. Her current focus is the environment.

“I mean, Miss Fonda said to me just yesterday, 'We have to have more people die,’” Tomlin spills. “That was a grievous thing for her to say … I just want to remind you, when you say things to me, I don't forget them.”

“Well, you’re not supposed to say them to ET!” Fonda replies, going on to explain what she meant. She considers overpopulation to be the biggest issue facing the planet today.

WATCH: Lily Tomlin Opens Up About Taking On Complicated Characters

“When we were born, there were about two billion people on the earth,” she notes. “There's seven billion now.”

When asked if there’s any topics she considers taboo to speak out about, Fonda says, “I certainly don’t.”

As for what’s left to accomplish for the trio, the sky’s the limit. Lear says he doesn’t keep one, big bucket list. Instead, he has one for every day of the week, for every week of his existence.

“Please don’t take my sunshine away,” he sings, as our conversation wraps up.

New episodes of Norman Lear's All of the Above premiere Mondays on PodcastOne. Fonda and Tomlin's interview will air later this month. For now, check out Lear's chat with comedian Jerrod Carmichael in the player below.

WATCH: Jane Fonda and Lily Tomlin Share the Secret Behind Their Youthful Looks