PROLEGOMENON to a dissertation on a neglected contemporary art form: the intermission.

Intermissions, let us take note, are an integral part of the great cyclical Rhythms that permeate all existence, and are as such, worthy of mystical awe. Just as in physical nature, night succeeds day, ebb tide follows neap, spring replaces winter; just as in our human sphere, sleep supplants wakefulness, and the Sabbath punctuates the week's toil; so, in the theater, intermission follows inevitably upon performance, bringing needful refreshment and abeyance from the strain and labor of cultural uplift.

What is less generally recognized is that intermissions are a rich form artistic expression, as audiences give vent to feelings and sensations long repressed under the obligations of theatrical attentiveness and courtesy; as they indulge fantasies and whims inspired by the artifal night of dimmed house lights; and as they exercise their simple needs to stretch, to breathe, to move.

What is even less generally recognized is that intermissions are no mere chaotic occurrences, devoid of esthetic composition or contour-they follow well-established formal principles as definite and significant as those of the fugue or the pas de deux .

The classical intermission, in fact, is a tripartite structure most readily understood as consisting of-if you'll forgive the introduction of technical terms so early in our discussion-an exodus , a development and a reseatification .

As one would naturally expect, each of these formal subdivisions has its own express content and function. The exodus , despite its vulgar identity as "The Charge Up the Aisles," is in most theaters taken at a tempo between adagio and larghissimo, and is the occasion for much recognition and reunion, to wit:

"Isn't that Senator Bootleg over there, behind the redhead?"

You mean the one with the mustache and the pinstripes?"

"No, silly, the bald one with the cape."

"Oh, there's Edna, Quick, what's here husband's name, I never can remember."

"I think it's Herman or Humbert or something like that-I know it begins with an 'H.'"

It is in the development that the themes of the intermission are variously articulated, and a number of devices may be employed. In elementary cases, the period is given over to extemporaneous and notably soporific remarks concerning the weather, the day's headlines, or how everyone is wearing blue this month. Eavesdropping, a fine art in itself, is cultivated in both its surreptitious and brazenly unabashed modes. A certain amount of flirtation and other amorous horseplay is usually observable as a counterpart to the main progressions.

A constant feature of all intermissions is the invariably prestissimo, often agitato, stretto of the libation seekers-the race to see who can get to the bar first. a taxing intellectual choice is also present, a dilemma the horns of which are represented by Peanut Chews and Raisinets: which shall nourish?

The development section is also that portion of the intermission that allows both for judicious escape-avoiding the impending torpor of the finale-and illicit entry, through the centuries-old practice of "second-acting." Other idioms in prevalent use are reading program notes, purchasing souvenirs, and calling the babysitter.

One of the chief pursuits of the development is the mid-evening appraisal; herein each member of the audience turns critic, assessing and debating the merits of the performance. The professional journalists, meanwhile, have mostly repaired to what is euphemistically referred to as the "press room," meeting with colleagues and publicists to discuss such fine points as whether or not the tutus in the "Swan Lake" are new this year, and fleeing from buttonholes who accost them with: "I saw you taking notes-you reviewing this? Waddya gonna say about the orgy scene?"

The reseatification brings the development to a more or less rounded conclusion and then recapitulates the themes of the exodus , often in reverse order. A prime source of excitement in this section is the effort to beat the odds and reach the final cadence-i.e., your seat-before the darkness unpredictably descends or the curtain rises.

Intermissions have a long history, though in the early days of public opera and ballet, the line between spectating and intermissioning was rather blurred, as patrons smoked cigars, consumed 10-course banquets and harangued each other with gossip all during the performance. The intermedii, intermezzos and entr'actes that were interspersed among the acts were in fact mini-operas, plays and ballets, so entertainment was nonstop.

This latter practice has been adopted in recent times by public television, wherein broadcasts of operas, plays ballets or concerts are succeeded in the breaks by testimony from such artistic authorities and scholars as Dick Cavett or Robert MacNeil. Commercial television, on the other hand, is almost nothing byt intermissions, as ad spots consume and ever-greater proportion of the time.

Here, however, it also is true, in accordance with the inexorable workings of Fink's Law, that program content and intermissions are rapidly approaching the point of complete indistinguished ability-is the ballerina part of the cast of "Les Sylphides," or an illustration of diet-cola efficacy?

There are indications lately that the study of the art of intermissions may be emerging from the obscurity in which it has so unjustly languished. One hears that the National Endowment for the Arts is seriously considering a massive seed grant for the establishment of a National Intermission Institute. Four American universities are now offering doctoral programs in intermission management and administration. In the next session of Congress, a bill will be introduced to set up a cabinet-level Bureau of Intermission Affairs. A new glossy magazine called "Mingle," devoted specifically to the concerns of intermission lovers, will appear on the stands within the next few months. And this summer, the American Intermissionary Association holds its third annual national conference at the El Paso Hilton.

Perhaps within the next decade or so we will finally see the intermission elevated to a place of proper respect among the great cultural institutions of modern civilization.