Writing a book is like running a marathon. You need to be fit to do it, mentally and, as far as possible, physically.

Writing a book is like running a marathon. You need to be fit to do it, mentally and, as far as possible, physically.

What drives me is a sense of urgency. We live in frightening times. Progress towards gender equality and vital battles to end discrimination on grounds such as race, age, sexuality and disability are stalling and in some places, reversing. This is happening because of the collapse of trust in nearly all public institutions, and in particular in politics and media, and the inescapable feeling that the current system isn't working for most people.

Studies show that women seeking power tend to be punished for doing so, because it goes against cultural bias. Women are expected to be likeable and pliant. We are also trained to expect any success we attain to come to us through men - by pleasing men, as good employees, good partners.

Our male-dominated culture tends to define success in terms of wealth, fame, power, the reaction of others. Women are fed a version that includes personal fulfilment through marriage and motherhood in addition to professional acclaim and of course we must look sexy but not too sexy and then graciously disappear when we hit middle age.

The system isn't working for most people and never has worked for most women.

One of the reasons I'm able to write books and still carry on with other work is that I do my best writing between 5am and midday.