If you called the singer Michael Jackson two-faced, he'd sue you for defamation because it's clear he's had far more than that. Strictly speaking, he's probably seven- or eight-faced by now. Wacko's flaking skin and collapsing nose were photographed in the unforgiving light of a courtroom during legal proceedings, which were followed by this week's snaps of him dangling a child from a Berlin hotel balcony and then escorting two veiled toddlers around the city zoo. It's possible, I think, that his facial rearrangements and his eccentric parenting are connected.
It has often been said that men who grow beards have something to hide and, if that's true, we can only guess at what guys who seek out a whole new set of features are seeking to conceal. Going under the beautifying knife is generally an indulgence of the rich, but we also tend to see it as a moral failing. If Michael Jackson's children were kissing each night the face he'd been born with, he might also be looking after them in a more conventional way.
A lack of realism about appearance and the ageing process must reflect a wider failure to engage with life as it's actually lived. Many of us don't like what we see in the mirror, but we either squint into it or rely on the occasional reflection from shop windows rather than starting over again. For this reason, a lot of laugh lines will have been creasing - among those of us who still have the face we were given on our birthday - at this week's warnings from doctors that Botox treatment, the anti-wrinkle injection favoured by the rich and famous in Britain and the US, may have long-term side-effects.
When historians look back at the culture which formed on the cusp of the 21st century, Botox will surely be one of the details which sum up an era of wealth and decadence. How hilarious it will seem to the readers and viewers of those future Schamas and Starkeys that people willingly injected themselves with a derivative of a deadly poison (botulism) in the hope of passing for younger than they were. What an even more perfect moral tale it will be if - as the medical profession now fears but pharmaceutical companies deny - these gravity-defiers were, in fact, potentially damaging their health.
Believing myself to possess the reflex cynicism necessary to journalism, I recently discovered that, in this area at least, I'm too naive. Watching a British woman TV presenter recently, I silently applauded her bravery. Her frozen mouth and creaseless brow suggested that the poor woman had suffered a stroke and yet was insisting on resuming her career. It was only when studio gossip suggested that she was a victim of Botox overdose - a medical complication which provided the plot for an episode of Absolutely Fabulous - that an alternative explanation for her expressionless delivery occurred.
For a long time, there was a feminist defence of cosmetic surgery, which was that the deterioration of men and women was treated differently by society. A crepe-faced man could prosper in business or in television, while the equivalently wrinkled woman would be replaced. But, increasingly, it's men who submit to the vanity syringe or scalpel.
Michael Jackson may be an unusually complicated case of self-hatred and reinvention, but Cliff Richard is among the men who have admitted to Botox, while Dale Winton has spoken of a facelift. Performers claim that this is necessary because their fans want them to look their best, but given that pop stars tend to be roughly the same age as their core audiences - so that tours of 70s stars play to fiftysomethings now - there may be a certain solidarity in rotting at the same rate. In the end, two-faced stars are doing it for themselves.
Let me say before the letters page does that I'm aware that even a dose of botulism sufficient to depopulate Oxford would only make a start on my own needs in this area, but the reasons for resisting are not just that it seems wrong. Crucially, it looks wrong too. In America recently, I noticed that a prominent anchorwoman now looks permanently as if she has just sat on a man's hand. Since September 11, it may be appropriate that so many New Yorkers in late middle-age wear a startled expression, but it's worth bearing in mind that this is a result of cosmetic self- indulgence rather than geopolitical concern.
Cliff Richard's preservation of his youthful looks was impressive in his 40s, but now the attempted choirboy's face on the pensioner's frame begins to look eerie and unnatural. There's a famous showbiz joke about George Melly commenting on Mick Jagger's wrinkles and the pop star insisting that they were laugh lines, to which Melly replied: "Nothing could be that funny." But, looking at these superannuated rockers now, you wonder if Sir Mick's relative acceptance of what his face was doing doesn't give him the last laugh on Sir Cliff, as well as allowing him to show his amusement.
Most of us have had the experience of reading a medical scare story in the news-papers about new research into some action - mercury tooth fillings or eating hamburgers - which we ourselves innocently took in the past. On such occasions, our eyes widen and brows furrow. Now it's the turn of the Botox men and women to worry. But is it an advantage or a disadvantage that - to the world - they'll look entirely unconcerned by it all?