Paulina Porizkova has a serious point to make about aging — and she’s baring all to make it.

On Tuesday, the 55-year-old supermodel took to Instagram to share a tasteful nude selfie taken in her bedroom.

“Today, on a serious note, thoughts inspired by the brouhaha around a sexy photo of @elizabethhurley1 …,” she wrote in the caption.

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“When I was in my twenties and thirties, the less I wore – the more popular I was. In my forties, I could walk around practically naked and illicit nothing more than a ticket for public indecency. At fifty, I am reviled for it. ‘Put on your clothes, grandma. Hungry for attention, are you? A little desperate here? You’re pathetic,'” she continued, pointing out the double standard that exists in societal beauty standards surrounding growing older.

“Why is sexiness and nudity applauded in a woman’s youth and reviled in her maturity?” she asks, and then provides an answer: “Because of men. Men are biologically programmed to spread their seed, inserting themselves into fertile containers which advertise their viability through youth. What does this say for men who do not want children? Men who have all the kids they wanted. Men who don’t want kids right this second? Unevolved,” she added.

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“And what does this say for women like myself, who need to be validated by the male gaze? Insecure,” she wrote, concluding, “The only thing that is pathetic here is allowing others to set your priorities. #sexyhasnoexpirationdate #betweenjloandbettywhite.”

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