The same might be said for Raeburn's work as a whole. He's generally classed as the top Scottish painter, and a selection of his pictures (about 60 from a vast output) is this year's festival exhibition at the Royal Scottish Academy in Edinburgh. Raeburn lived from 1756 to 1823. He painted only portraits - of the philosophers and scientists of the Scottish Enlightenment, of gentry and lawyers, their wives and children, of lairds sporting the newly revived and fabricated formal tartan costumes, of Walter Scott himself, several times. The Skating Minister isn't typical. It's an idiosyncratic one-off in an uvre for which larger and more canonical claims are often made, as they surely are by this exhibition. Raeburn should stand, it's hoped, not merely as a local hero, but as one of the greats, an artist of European stature.
I'm not sure how much point there is in this sort of league-tabling, but if you consider that two of Raeburn's nearest European contemporaries were Goya and David, both of them also enormously strong in portraiture (among other things), that gives an idea of how stiff the competition is. But comparisons are tricky. In an age of artistic and political revolutions, Raeburn wasn't a revolutionary artist. He worked at a distance from Continental currents, though he went to Rome in the mid-1780s. He should be taken, to start with at least, on his own terms, which aren't admittedly all that promising - a professional and increasingly successful society portraitist.
And on these terms he is certainly remarkable - a remarkably sophisticated, vivid and virtuosic painter. You can see distinction in some of the earliest work on show here, painted just after his return from Italy: how, for instance, Raeburn can turn the standard repertoire of portrait poses into a highly inventive composition. In The Archers, a double portrait of two young men, the canvass is dominated by the firm geometry of the drawn bow, its arc, strings and arrow. Meanwhile, a corner of the rather stiff portrait of geologist James Hutton has a sudden patch of superb painting in the little still-life of geological specimens, made up of (to quote the catalogue's description, which is a little still-life in itself) "a chalk-fossil, two examples of mineral veins, a druse, a septarian nodule and a breccia". These strange objects release some very pure colours and free brushwork.
This freedom breaks out wherever opportunity occurs - in the folds and tassles of a judge's red robes, in the sketchy skies and views that make the background to an outdoor portrait, in fluid white linen shirt-fronts and bonnets, in the pattern of an Indian shawl or the haze of a fur, in the swelling flesh of a fist. Raeburn can paint with startlingly modern flatness - a gentleman's coat and breeches are laid in with quite unmodulated maroon. The striped dressing-gown of the astronomer John Robison is almost carved in bright scarlet. He can introduce into generally sub-fusc schemes the most resonant colour harmonies. In the portrait of the fiddler Niel Gow, the purple of the coat, the pink and green tartan trews, the orange of the violin's wood make a combination that - released from its sombre context - might have pleased Matisse.
Occasionally Raeburn's painterly thrust proved at odds with the needs of the job. For a time in the 1790s he used stark contre-jour effects, having his sitters virtually back-lit, so that the edge of the face is a blaze of brightness, and the rest modelled in a softer, secondary light. This high-contrast treatment turned out not so popular with the clientele, not a firm enough likeness, and he dropped it (it does result in a rather disgusting glisten). But it displays something that Raeburn didn't abandon, but cultivated ever more finely, his mastery of illumination. A favourite device: the upper half of the face is almost lost in the shadow of a hat or bonnet, with the shaded features delineated from below by a glow reflected off the cheeks.
Psychologically, Raeburn may not be penetrating, but he is an exceptionally sensitive operator. He deploys subtly asymetrical expressions, one side of the face saying something slightly different from the other, that resolve into complexity. The fugitive blurs with which he joins the facial features together lend a persuasive vivacity. The face of Ann Fraser is held before us in eager transition; that of Sir Patrick Inglis at a moment of indecision between humour and pomp.
So Raeburn has many original gifts and expert felicities. He's also capable of putting his bravura hand to smooch and monstrosity, as (respectively) in the melting, tits-out swoon of Mrs Robert Scott Moncrieff, and the swaggering tartanry of Sir John Sinclair of Ulbster - the kind of performances that make him look less like a hint at Manet, and more an awful premonition of the oil-debauches of John Singer Sargent. But it's not these excesses that put the real limitation on Raeburn's work.
It's his moral soft-focus. He has none of those dramas of identity that the greatest portraiture plays out, the tensions it can reveal between individuals and their social role, the clothes and the flesh they find themselves in, their self-presentation as someone being portrayed. Raeburn's portraits are unconflicted. I don't say that his pictures entirely surrender to the direct social or physical flattery of his sitters. But these people are always absolutely at home in their selves and their worlds, and Raeburn's art, including the finest things in it, is devoted to confirming this state of affairs.
I mean, its very freedom and sensitivity are devoted to moderating anything that might be obtrusive. It denies the oddness of fashions and of bodies. There can be few more ridiculous outfits in the history of clothes than full dress tartan, yet what an opportunity it offers to an artist who would take the strain of its extravagant artifice. But in Raeburn it's the occasion for admittedly brilliant but glancing effects. This is true of almost all his costumes: no confidence in particulars, but an appeal to the eye that says "you know how it goes". Something similar happens to his human presences: psychologically mobile, but it's as if the personality had been abstracted from the actuality of a body. The expression is vivid but the features are generalised, their singularities suppressed.
If you compare Raeburn with a Scottish portraitist of an earlier generation, Allan Ramsay, you see the difference. There is no face in Raeburn to compare with Ramsay's porky jowelled image of the philosopher David Hume, or the literally wart-and-all picture of Mary Adam. Raeburn remains broadly humane, intelligently sympathetic, but even in his most powerful portraits, like those of Mrs James Campbell and John Clerk of Eldin, he never conveys the sense of surprise - which even quite standard portraiture sometimes can - that yes, this body, this character once lived. In Raeburn the human presence is subsumed into the painting; neither offers any resistance to the other. This is his at-homeness.
So, he's bound by the limitations of the profession, and the ethical climate of moderation, in which he worked and thrived? Sure he is, and not exactly to be blamed for that, but it puts an edge on the larger claims that are made for him. Raeburn doesn't escape from the sociable embrace of his genre, from making pictures of "people like us". And I suppose it's an extension of this embrace that partly sustains his reputation in Scotland: praise for Raeburn is hard to separate from honour to the ancestors, and feeling warmly familiar with these folk whose portraits are designed to make them familiar with themselves. In its clipped and humorous way, there's more of the essential tension of portraiture in The Skating Minister than in Raeburn's more central work. An oddity, annoyingly popular, but still Exhibit An
At the Royal Scottish Academy to 5 Oct (0131-225 6671); and at the National Portrait Gallery, London, from 24 Oct to 1 Feb 1998