Harriet Walker: Fifty years on, let's embrace once more the spirit of Helen Gurley Brown

Like any liberated modern woman, the Single Girl feels no need to lie about her age: she is 50 next year – and my, hasn't she aged well?

It's a half-century since the publication of the original "lipstick feminist" and indefatigable Cosmopolitan editor Helen Gurley Brown's Sex and the Single Girl, but its manifesto is far from outdated. If anything, we need her words more than ever.

Gurley Brown was the first to suggest that the radical feminist ideologies of the time – the shunning of men, the maternity myth – might not have been accessible to the average woman; she offered not ethics but everyday solutions. Some women, she reasoned, might enjoy the company of men; some women may want children; and some women may enjoy sex.

Her words are invaluable now as a generation of women grows up in a world dominated by, yes, men but also by porn culture, celebrities and reality TV. It's getting harder and harder to find female role models; we were offered Carrie Bradshaw, who is often held up as the latter-day patron saint of the Single Girl but just turned out to be obsessed with herself and her shoes.

No, the women who people popular culture these days are mere production-line incarnations of the independent, sexually confident creature that Gurley Brown spoke of. They have the semblance of that independent spirit, but are shot through with discrepancies and hypocrisy. They are overly tanned, packed with Botox and silicone, scantily clad and stupid: dolls formed from the heads of men in suits.

Gurley Brown advocated dressing up and wearing make-up; she was no apologist for the weaknesses of the flesh, but rather a pragmatist about the lure of companionship. And her approach strikes a similar chord in an age of "post-feminism", as Forbes magazine dubbed it last week, as it did in the 1970s, when millions of women staggered, blinking, out of the kitchen. They were anxious and uncertain of how to act – just as we are now. Like it or not – and I don't deny the progress we have made – many women are still just as scared of so-called "feminism" and its adherents as they were back then. Beyoncé won't even admit she is one.

To make a concept more palatable is not to dilute it: Helen Gurley Brown knew that. So, on the birthday of her book, let's wish her and the Single Girl many happy returns.