The wondrous nonslip slipper.

In ballet, we use the term classic with profligate carelessness. We even call ballet itself--to distinguish it from other forms of theatrical and social dance--"classic" ballet, and say, rather meaninglessly, that it employs a "classic" technique. Our concept of a ballet "classic" is just about as amorphously vague. But just what is a classic?

A useful enough kind of dictionary definition of a classic, or of classic art, might be either something possessing a high quality that is universally recognized and unquestioned--although what quality can ever be totally safe in its recognition, faced with the carping questioning of the occasional critic?--or something exhibiting the accepted qualities of "classic art" in being simple and harmonious. Even here, what one person may find simple and harmonious may not elicit the same response from another. We are in subjective territory here, while a classic might surely be properly presumed to be a more objective statement of art or of life.

One thing that must be clear about a classic is some degree of longevity--a classic must last. We even obtusely recognize this essential quality in that special oxymoronic phrase "instant classic." And a classic must not only endure; it must speak to different generations, sometimes with a different voice. We don't hear Bach with the ears of his contemporaries, but the music sustains in us, or in enough of us to matter, a credible response that justifies calling, say, the Brandenburg Concerti classic.

In this sense, for all our talk about classic ballet, I suspect that classic ballet has very few real, twenty-four-carat classics. What makes a ballet classic anyway? Opinions differ, but to me it seems that a true classic demands the perfect (or virtually perfect) matching of music and choreography, and possibly theme, in a lastingly meaningful fashion. Now, of course, individual taste immediately rushes into play--what I may find classic you may find rubbish. But informed consensus can have a role here. No one can prove that Leonardo's Mona Lisa is an eternal masterpiece. To consider it second-rate is not necessarily to be wrong, but it is to go absolutely counter to intelligent taste over the centuries.

Frederick Ashton's Cinderella has not stood the test of centuries--indeed, it has rather more than a year to go to notch up its first half-century, while Sergei Prokofiev's slightly older score is still only fifty-two years old--but seeing the ballet four times over the space of a few days when the Royal Ballet brought it to the Metropolitan Opera House this July made me feel, rather unexpectedly, that here was one of the few real classics--of twentieth-century ballet. Unexpectedly? Yes, because even though I saw its very first performance in 1948, and have been lucky enough to see it many, many times since then in London and in New York City--although not, oddly enough, for a few years--its charms, beauties, and sheer resilience struck me afresh, as if for the first time.

And this realization of its singular quality appeared all the more remarkable because it seemed to me that the ballet itself was in less than first-class condition, both decoratively and choreographically. And although it was well enough danced, I submit--despite the splendid portrayals in the title role by both Leanne Benjamin and, perhaps particularly, Darcey Bussell--it has been danced better, and certainly acted better, in the past. Yet, for all that, it glistened with glory.

Ashton was at the height of his powers in 1948, the same year of his Scenes de Ballet to the Stravinsky score. And some of the complex yet deliciously simple-seeming ensembles in the full-evening work--the first, incidentally, ever to be created for British ballet--show a strong kinship with the earlier plotless masterpiece, especially in their use of sequential and metachronal movements. The strange thing is that, like so many of Ashton's ballets--most of them in fact--it was originally received with somewhat faint and damp praise. It was liked by most, yet dismissed a little patronizingly, certainly in England and even in America, where it was seen during the Royal Ballet's first New York season in 1949.

Of course, Ashton's ballets are notoriously difficult to take in on first sight. Luckily, I had yet to start reviewing, but I myself was grievously disappointed at the premiere of Scenes de Ballet, and, less luckily, when The Dream was new in 1964, I was prominent among the critics left blind and niggling by its Mendelssohnian charms and its Shakespearean virtues.

Cinderella I always loved, but I am far from certain that before this present Royal Ballet visit I was fully aware of its pure classic perfection. Prokofiev's score is surely much more inventive than his own earlier Romeo and Juliet, but, in any event, Ashton has matched it, amplified it, and eventually transcended it in an act of extraordinary artistic transfiguration. There is an amplitude to Ashton's concept, embracing fairy tale and English music hall, Maryinsky form and fireworks, and British formality and balance.

Yes, I always loved it--its clowning, the rapturous beauty of its love duets, the spontaneity of its Fairy variations, the interweaving of its corps de ballet patterns, the warmth of its dramatic concept. What was there not to love? Yet it took until now for me to realize that it is not just lovable, it is immeasurably great, one of the uniquely superb works of twentieth-century dance, beside which most choreography seems at best futile, at worst presumptuous.

So it is--I am sure of it--a classic by any standards you can reasonably formulate. So will it last? Will it be like Giselle or Bournonville's La Sylphide? Who can tell with something as fragile as ballet, something always dependent on the kindness of ever-stranger strangers and ballet masters? The Royal Ballet hardly treats Ashton with the same earnest respect and attention New York City Ballet bestows on Balanchine. And choreography, itself? Well, David Lichine put it well when he said "choreography is like moisture in the mouth of an orator."

One thing I do know. This Cinderella certainly deserves a niche in American repertory. I think it would be a very suitable and useful addition for New York City Ballet--it has the dancers and could easily master the style, and it would add to the range of the company and the pleasure of its audience. As for the Royal--it could well check on a few video records and with a few of the older dancers (particularly Alexander Grant) and get it redesigned. Decoratively, classic or not, it now looks like a provincial English pantomime. Which is a pity.

Clive Barnes is a senior editor of Dance Magazine.