And - just as with winning the lottery, or becoming famous - there is no manual for becoming a woman, even though the stakes are so high. God knows, when I was 13, I tried to find one. You can read about other people's experience on the matter - by way of trying to crib, in advance, for an exam - but I found that this is, in itself, problematic. For throughout history, you can read stories of women who - against all odds - got being a woman right, but ended up being compromised, unhappy, hobbled or ruined, because all around them, society was still wrong. Show a girl a pioneering hero - Sylvia Plath, Dorothy Parker, Frida Kahlo, Cleopatra, Boudicca, Joan of Arc - and you also, more often than not, show a girl a woman who was eventually crushed. Your hard-won triumphs can be wholly negated if you live in a climate where your victories are seen as threatening, incorrect, distasteful, or - most crucially of all, for a teenage girl - simply uncool. Few girls would choose to be right - right, down into their clever, brilliant bones - but lonely.