In a weird way, the tsk-tsking over a pair of high-fashion ad campaigns featuring Joni Mitchell and Joan Didion reminds me of the flap over a pregnant Demi Moore posing naked for Vanity Fair in 1991.

I remember talking about the Moore cover at the time with a colleague who admitted to being a little bit shocked. Not at seeing a nude woman - we see nude women all the time in movies, magazines and art. It was the fact that she was so very pregnant that he found disturbing. A nude pregnant woman isn't an aesthetic object or figure of fantasy in the same way a Playboy model or Goya's "Naked Maja" might be. She's a real person (albeit a gorgeous movie star) with baby onboard.

Joan and Joni didn't have to take it all off for Celine and YSL, respectively, to cause the same kind of stir. All they needed to do was to show their aging faces in moody, black-and-white fashion shots without (it seems) much makeup or retouching. Each looks unapologetically old - Didion is 80 and Mitchell, 71 - and completely at ease with themselves. I guess those naked faces are a different type of nudity.

Ultimately, time catches up with us and there's no way around it. We won't look youthful forever. Stopgaps like Botox, lasers and surgery have their limits. People who have work done look - well, they look like people who have had work done. Who's more attractive, Joan Didion or Joan Rivers?

It's our reaction to those faces - not to mention the ones we see in the bathroom mirror - that's the problem. We like to look at pretty people, and that's what Madison Avenue and Hollywood dish up 99 percent of the time. When they give us something different, what are we to think?

I, for one, had mixed feelings about the Mitchell ad in particular. Joni is a boomer icon. I've long followed her career and still love her music. She was so striking and unconventionally pretty back in the day; I found it disconcerting to see her as she is now.

Am I brainwashed by the beauty culture? Or spooked at the reminder that I'm aging right along with her, and have my own wrinkles and sags to contend with?

Yet on another level, it's inspiring to see the unvarnished photos of real older women who seem comfortable in their own skins. Mitchell and Didion challenge us to look beneath the surface and rethink our definition of beauty. "Will you take me as I am?" Mitchell sings in "California." It could be her refrain now.

"We (women) don't really have any idea of how we ought to look anymore, just how we're told we ought to want to look," says Anna Quindlen in her book on aging, "Lots of Candles, Plenty of Cake." Mitchell and Didion, of course, have the help of chic design houses in figuring it out. But perhaps their radical self-acceptance can be a lesson of sorts for the rest of us.