Rachel Dolezal, the 37-year-old president of an American organisation to advance black people - NAACP - has been much disparaged for pretending to be a black woman: "masquerading" was the word used. Her fantasy of being an oppressed black woman was revealed to be just that - a fantasy - when her parents went and "outed" her as 100pc white, with mostly Nordic and German ancestry.
It was a bit of a daft pose in the age of the TV interview and the world wide web, and it hurt her parents that she seemed to have so resolutely rejected them. But I don't see that it was such a terrible thing to do; probably far more people than is ever realised do live out lives in a fantasy identity. And it's very easy for a fantasy to somehow acquire a reality of its own.
When I was a youngster, I sometimes used to say that my elder brother, who bore the exotic name of Carlos Patricio Santiago, was born in South America. He wasn't, but my father had spent many years in Chile, and named his eldest son in honour of a country he had grown to love. I repeated the fairytale quite a few times, until I almost began to believe it myself. It was only when I was quizzed about how many years my mother had spent among the exotic gauchos and gorgeous gringos that I quietly let the story drop.
The same Carlos wasn't immune to fantasising himself. He had a great fascination with World War Two air aces, and after he crashed a car in the 1940s, and was on crutches for some time, he liked to stand up for ladies on the Dalkey bus, recalling his gallant air forays over Berlin. (The Dalkey bus at the time often featured Anglo-Irish ladies with bejewelled RAF brooches on their costumes.)
Numerous people, throughout history, have passed themselves off as something they were not. After the annihilation of the Czar and his family in 1917, numerous Romanov princes and Russian aristocrats were to be found driving taxis in Paris or running restaurants in Hollywood: some were real, many were not.
After World War II, it was not uncommon for Jews who had managed to escape the horrors to try and wipe out their nightmare memories with a new non-Jewish identity. Madeleine Albright expressed some critical feelings about her parents' generation of European Jews who sought to blot out their original identity and reinvent themselves - but it was surely understandable, in context. And how many black or mixed-race people, in America and South Africa, sought to "pass" as white, back in the day? An entire musical featured this story - Show Boat - the divine Ava Gardner starring as part-black in the original movie.
Many famous "Irish" people are not Irish at all. The most iconic Irishwoman in history - Maud Gonne, who inspired not only Yeats but an entire generation of Irishmen to revolution - had not a single drop of Irish blood in her veins. My teenage hero, actor Micheál MacLiammóir, was born Alfred Wilmore in East London, but let on, all his life, that he was from Cork, and fabricated his very own Cork accent to go with the story.
Peter O'Toole always said he was from Connemara, but actually, he was from Leeds, and any Irish link was tenuous. Yet he genuinely thought of himself as Irish - I remember being with him on one occasion when he talked rugby all afternoon, supporting the green jersey. Similarly with the writer Patrick O'Brian: he liked people to think he was Irish, though he was an Englishman - Richard Patrick Russ - and he seems to have identified with the Irish-Catalan character, Stephen Maturin, in the naval stories he wrote. So what? He was a storyteller.
Fantasies about gender identity are nothing new: there have been men who wanted to be women and women who wanted to be men since the beginning of time. Modern surgery and hormone treatment have made this possible (up to a point: you cannot change your chromosomes any more than you can change your blood group), and "transgendering" is now considered acceptable, and even fashionable.
Indeed, it's thought unkind to query whether this, too, is a kind of make-believe. Dr Paul R McHugh, Professor of Psychiatry at John Hopkins University, claims that transgendering is a form of "body dysmorphia" (having a distorted view of your body, as anorexics tend to have), and a mental disorder based on fantasy. It's all in the mind, he says.
Still, on the live-and-let-live principle, if individuals want to live out their lives in a different identity than the one they are born with, who are we to judge, as Pope Francis once said? Biologically, Rachel Dolezal is not a black woman: but she says she feels "culturally black" - she is the mother of a mixed-race son - and that from the age of five she identified with black people. Let it be.