Gloria Steinem is a feminist icon, a champion of women's rights since the days when women didn't have any. The American activist and author will be 82 next month, and from the early Sixties onwards she has never stopped writing and campaigning for her core causes: birth control, equal pay, an end to violence against women, civil rights and social justice.
Does the fact that she is still crusading for these beliefs after all this time mean the women's movement has been unsuccessful?
Not a bit of it. "Feminism has not been a failure," she tells me. "We have achieved a great deal, but we still have a long distance to go.
"Perhaps one of our greatest achievements is to know that we are not crazy.
"In the beginning, the very idea of not conforming to a feminine role meant there was something wrong with you. You were supposed to be a good listener, a secondary person, someone who made the tea."
We meet in the offices of her London publisher, where Gloria is both amusing and amused, smart and erudite.
As always she is dressed in her uniform of black Joseph trousers and black sweater, with a Navajo silver belt on her tiny hips.
She's still a glamorous figure - a woman who dislikes plastic surgery but dyes her hair.
She hated being called the "pin-up girl of the intelligentsia", but famously used her looks to work undercover as a Playboy bunny in 1963 to expose the seedy underside of that world.
She also worked for the CIA and co-founded Ms, one of the world's most influential feminist magazines.
She has beaten breast cancer, nursed her sick mother as a child and cared for her dying husband as an adult.
Today, she seems to be more in demand than ever and lives a sharply curated life - she has learned to excise what does not matter. She does not cook, she can't drive and she never travels with "more than I can carry".
When it comes to her legacy, she's typically modest.
"Have I made a difference? I can't judge because I don't know what the world would have been like without me," she says. "But I get immense satisfaction from someone just coming up to me in the street saying that something I did or something I had written helped them. That means a lot."
Here, she reveals the accumulation of decades of hard-won wisdom at the sharp end of the sex war, with her unvarnished guide on how to be a woman.
1. Keep Your Own Name
I got married, when I was 66, to David Bale. [A businessman and environmentalist, and the father of actor Christian Bale, David died of cancer three years after they wed.]
My husband and I were together an alarmingly short time before we got married. It was impulse.
I thought the women's movement has struggled for 25 years to allow marriage to be an equal partnership, so I no longer had to give up my name, my domicile, my credit rating, so why not? No one ever called me Mrs Bale.
If they had, I would have said: "My name is my name and his name is his name. And since you are asking, my name is Gloria Steinem."
Actually, he used to get called Mr Steinem, which he thought was funny.
2. Take Care On Twitter
I became the centre of a Twitter storm recently because I said young women would back senator Bernie Sanders instead of Hillary Clinton [as the Democratic nominee for U.S. President] because that's where the boys are.
I was talking about power - what I meant was the power is in the hands of the men - but it was assumed I was talking about sex.
I'd never say such a denigrating thing about women. I wouldn't dream of it, but it is my fault - I should have been more careful.
3. Ignore Ageing
I am trying very hard to understand mortality because being 80 doesn't feel any different from being 40. It is still a bit of a shock when someone says I am 81. What?
I tell everyone in the world my age because I just don't believe it myself.
4. Make It All About You
Far too many people are looking for the right person, instead of trying to be the right person.
5. Never Waste Time
That was my biggest mistake. I continued for too long doing things I already knew how to do.
As a writer I was doing stories I was assigned instead of ones I thought were important. The wasting of time is the thing I worry about the most, because when you get to my age, you realise time is all there is.
6. Live Your Own Life
When I said women have become the men we once wanted to marry, I didn't mean it deeply. I just meant occupationally, because I think in the past, women who wanted to be writers or lawyers themselves married a man who was a writer or a lawyer.
But I have yet to be on a university campus where most women weren't worried about some aspect of combining marriage, children and a career. And I've yet to find one where many men were worrying about the same thing.
7. Refuse To Fear Fear
When you attempt something new, there is always fear. A couple of helpful slogans for me have been these: "Follow the fear" and "Fear is a sign of growth".
8. Follow your instinct
Working in Manhattan in the Sixties was like Mad Men, only worse.
I went to J. Walter Thompson for an interview, which was the biggest advertising agency at the time. They explained that I could not work with the clients because clients did not want to work with women. I could do research.
The same was true at Time magazine. Men write, women research - that was the hidebound system.
If you were not subservient, you were not giving men their due. Originally I wasn't disillusioned because my expectations were not very high. Then some unconscious part of me said no, I don't want to do this. It is unfair.
I've seen enough change to know that more will come.
9. Be Yourself
We grow neither better nor worse as we get old, but more like ourselves.
10. You Can't Have It All Yet
Yes women can have it all, a career and a baby - but not until men have both, too. What I mean is, not until men are equal parents. At the moment it is still a double burden for women, one that's very difficult.
11. Plan Your Finances
I very much worried about money until I was about 50. I always imagined I would end up being a bag lady, and I tried to deal with this by saying, well, at least I'll organise the other bag ladies.
It was only after 50 that I began to save money. Now I have a home that I own and, whatever happens, I won't be a bag lady any more.
12. Fight Botox Pressure
The increase in plastic surgery and Botox really worries me. I don't see these procedures as anti-feminist.
What I feel is there is no individual fault, it's a collective social pressure.
I'm not for or against it, but I would like to remove the societal pressures that create it.
It seems to me that to blame the individual is a bit like blaming the victim for something that is just a pressure in society. There is huge pressure on everyone.
13. Turn old Lovers Into Friends
Especially if you not only loved but liked each other, too.
This is a big one that I try to tell students. It might take years to get over whatever the imbalance was, but the truth is the two of you shared something that no one else knows.
And you will always have that. It is never going to go away.
14. Don't have regrets
When people ask me if I regret not having children, I can feel the pressure to say "yes".
But I don't and I never did. When I was much younger I assumed I had to have children. I assumed everyone had to have children.
But someone said once that not everyone with vocal chords is an opera singer. And not everyone with a womb needs to be a mother.
When The Pill came along we were able to give birth - to ourselves.
Even today I still feel such gratitude towards the Pill, and I think there are millions who feel this.
* Gloria Steinem's memoir, My Life On The Road, is published by OneWorld