THE ''School of London'' is not really a school. It is simply a label that appears to have become firmly attached to a number of artists who have, since about 1940, spent long periods, if not entire careers, working in the British capital. Like most art labels, this one is useful as quick identification rather than for aptness, though at least it makes no attempt to define a shared style.
In fact, the artist who coined the label, R.B. Kitaj, has also described the ''school'' as ''a herd of differing loners.''
A major exhibition of six of these loners, called ''From London,'' has been impressively staged at the Scottish Gallery of Modern Art, Edinburgh (in good time for this year's Arts Festival). This selection of work will also be traveling to Luxembourg; Lausanne, Switzerland; and Barcelona, Spain. (See dates at right.)
In an attempt to define what these artists have in common, art historian and critic David Cohen, in the catalog essay, writes of the ''isolated, tenacious, psychologically intense, 'untimely' principles of the School of London....'' But these traits - even the ''untimeliness,'' or anti-avant-garde stance, which is arguable, are scarcely unique to these artists.
Most of them are scarcely unknowns. They are Kitaj, Francis Bacon, Lucian Freud, Leon Kossoff, Michael Andrews, and Frank Auerbach. All are still alive and working except Bacon. Kitaj was recently seen in a major retrospective staged in London, Los Angeles, and New York. Kossoff is representing Britain at this year's Venice Biennale. Bacon and Freud did the same in 1954; Auerbach in 1986. Only Andrews, by far the most ''English'' of the six in both family origins and in the atmosphere of his large landscape paintings, still awaits full-scale international recognition, though he has been seen in many group shows around the world.
The six artists are painters. They are not, for example, conceptual or performance artists. Their work is figurative, not abstract. Some of them had teachers in common, or went to the same art school. Most of them, at least at some point, have been friends, or have had friends in common. They have painted or drawn portraits of each other. Most of them have expressed admiration for the aggressively cruel images of Bacon's self-consciously grotesque paintings. Bacon was the ''old man'' of the six, born in 1909. Freud (a grandson of the psychologist) was born in 1922, and the remaining four were born between 1926 and 1932. Kitaj is the youngest.
They are a cosmopolitan group in that they reflect the cosmopolitan nature of their chosen city. Bacon came from Ireland and spent some time in Berlin. Four of the six are Jewish: Auerbach and Freud were both born in Berlin. Kitaj is an expatriate American. Even Kossoff, who was born and bred in London, had Russian immigrant parents. More than the other artists, his subject matter is London in all its gray, dowdy, anonymous, back-street-ish indistinction. But he does not paint in a manner that is unmistakably English. The urban moil his paintings evince may hint at admiration for the paintings of English painter Walter Richard Sickert. But the way Auerbach's images emerge out of an apparently inchoate welter of heaving paint, has more to do with the Flemish Expressionists, or even with the Viennese painter Oskar Kokoschka, than with any recognizably English tradition.
Auerbach's paintings are virtual monuments to the frustration of moving and building and scraping down paint in the willfully determined effort to - perhaps - arrive at meaning or even at some image. Stephen Spender described the human subjects in Auerbach's paintings - which have an almost impenetrable accretion of paint that initially appears quite similar to Kossoff's style - as ''like refugees conscious of concentration camps.''
The Holocaust is also a preoccupation of Kitaj's, but his art is different from the others in its fragmented presentation of what appear to be stories. Bacon insisted his paintings were devoid of narrative content (an insistence Kitaj has called ''a real bore''). Bacon described them more as a violent assault, by means of ''the texture of paint'' on the viewer's ''nervous system.''
Freud's later work identifies the very application and feel of his oil paint with the disturbing vulnerability of human flesh. This makes an immediate, aggressive impact that renders any hint of narrative either peripheral or nonexistent. Kitaj's discursive paintings, however, lead the viewer down intriguing alleyways of experience, memory, reading, fantasy, passion, art theory, and intuition. He does not accept that an artist is someone confined to a studio or locked in an exhaustive struggle with paint and motif.
It is interesting that the book that accompanied his recent retrospective is enhanced by small dissertations he has written on his pictures. He has said that he prefers viewers to arrive at their own conclusions; but his own words never fail to shed light on his complex thought and processes.
Odd man out
Kitaj seems the odd man out in this London School exhibition - although Andrews has pursued, with no less a conviction of his separateness, what he terms his ''mysterious conventionality.'' Although his pictures, usually landscapes, are far from being a violent confrontation with the viewer, the movements and skins of paint on his usually large canvases are primary and self-conscious. He uses both oil and acrylic paint not thickly but with the expansive freedom and thinness of watercolor, that traditional English landscape medium. The tensions in his work save it from banality. These are the tensions between scale and intimacy, between sweeping generalities and precise details, but above all between a realism as convincing as a kind of old-fashioned tourist billboard (''Come to Misty Scotland by Rail'') and an original exploration of the sensitive, exhilarating potential of paint itself.
A ''herd of differing loners'' indeed.