FOR A SECOND, for the briefest moment in the history of western male attire, it looked like all rules were off. Anything was possible, and, in the words of William S. Burroughs' favorite prophet, Hassan i Sabbah, everything was permitted, nothing was real.

In other words, at public occasions, except for things like board meetings of the American Cynamid Corporation, any clothes became acceptable. One could dine, wed, gamble, grieve and garner honors in jellabas as well as four-in-hands; plus leather bondage straps, Quina shirts that look like you've got them winched down snug to your underwear, lame and grommets and rivets and epaulets; jumpsuits and drawstrung Berber pantaloons; "Buns" underpants that would do for the male posterior what Howard Hughes did for the Jane Russell anterior, quadri-pleated British Army Hun-stompers; knee-high tree surgeons' lace-up boots; anything! Everything!

One didn't dress, one chose a costume. One became a revolutionary, or Ralph Nader, or divinely decadent, sort of an M Street version of Harry Crosby. Even the hipper Brooks Brothers faithful lapsed into sell-joshing: "Christ, I can't help it. I keep swearing it's going to be Guccis and Ralph Lauren from here on out, but then I'm walking down L Street . . ." Everybody was in show biz, following the dictum of the late Seventies: If you can't be good, be famous. If you can't be famous, at least try to dress like it.

That's the way it was.

That's not the way it is.

In the July 8, 1977, Daily News Record, the men's equivalent of Women's Wear Daily, Clara Hancox writes, in her column, "Hancox Here," that: "It's that peculiar and uneasy time again . . . [ellipses hers] the time when busy people actually find time to stop and think a little . . . to fish around for a feel of what's happening around the market. Maybe there's something they missed? Maybe there's a new goose appearing on the scene . . . and it's in the act of laying another golden egg?"

This tone of holocaustic messianism is echoed by men's fashion writers in Men's Wear, Gentlemen's Quarterly, Esquire, the ads and the market research. Two words keep appearing in the ad copy: "classic" and "confidence." Could this be because we have neither anymore? What we seem to be seeing is an industry-wide ego regression to the 1950s. As one ad puts it, trying to foist off both old bottle and old wine: "It whispers quiet British styling - SHOUTS VOLUME AND TURNOVER."

Sportscoats are back! Bermuda shorts! Even that old pseudo-pukka-sahib badge of upward suburban mobility, yes, madras. One reads that collar pins add crispness. Halston promotes the "Halston impeccable blazer suit for today's captains of industry [italics mine]. Gentlemen's Quarterly has concocted "post industrial chic," a phrase which would have pried a few smiles out of the original captains of industry, Carnegie, Rockefeller, etc.

"The juxtaposition of luxury and practicality is an intimate part of the Seventies sensibility," advertises an outfit called Pinky and Dianne Ltd. One senses a renaissance for the shorter-tip collar, Fifties-style, even the tab collar. One can go out wearing Bass Weejun loafers and a LaCoste shirt without fearing that he'll be mistaken for Richard Nixon's lawyer.

In short, profiles are low and anxiety is high. The idea is to be a right young man first, and a bright one second. With less money around, one makes more conservative investments, as Lord Keynes pointed out. One buys business suits, non-pleated-front trousers, scarcely venturing even a Daks top, and cuffing the bottoms. Last year, generally slow for men's retailers, Brooks Brothers boomed. Their stock is low-risk, as they say on Wall Street. And, in the I-Ching-like language financial analysts resort to in a down market: "In times of uncertainty, investors move to the sidelines and adopt a wait-and-see attitude." Finally, the Carter administration has not had its expected effect on men's wear - no sudden upvaluing of leisure suits, doubleknits or even clothing bags as accessories to be draped on the back, like the royal ermines, on occasions of state. But then, the Carter administration has not has its expected effect on anything.

To sum it up, nobody knows what's really going on in men's fashion. However, this will not hush the fashion experts, who exceed even out-of-office politicians in understanding what the American people really want.

What's interesting here are the reasons for the percennial failure of men's clothing to conform to say rationality. They are worthy of note to any man who is intelligent enough to remove the shoe trees before he makes his second try at getting the shoes on. There must be thousands of them.But if you've never considered clothing in terms of theory or philosophy, try on the following for size. (Don't worry about the color, it'll look differnt without the neon lights. The waist? We got a tailor. Whaddyamean nobody's wearing these, we can't keep them in stock . . .) The Fallacy of Self-evident Truths

Without getting too heavy here, let's just say that for the last few thousand years people in our part of the world have liked to base their arguments on self-evident principles, such as: this is either a piece of paper, or it is not a piece of paper. Who could argue? This is one reason the Founding Fathers said those truths were "self-evident" that men are entitled to life, liberty and so on.They were wrong, of course, but it sounded nice.

In fact, this mentality enchains us all, even in ephemera such as fashion, even in cultural beckwaters such as an enlisted men's barracks in the United States Marine Corps. In 1964. On Okinawa, known to us as "The Rock."

Hidden in our wall lockers, there is at Camp Schwab, were civilian clothes. Occasionally, I don't know why, we were allowed to put them on, like the Sioux Indians getting permission from the U.S. Cavalry to wear their ghost-dance shirts.

I was a college kid. I had a brown herringbone tweed jacket, a blue buttondown shirt, a red-and-blue silk necktie and grey flannel slacks. Space does not permit descriptions of the Okinawan-tailored fantasies of my fellow grunts - the side-buttoned bolero pants with ten-button, sateen-lapelled, double-breasted, gold-flecked puce morning coats over mock-lizard nylon body shirts, and so on. What I reacall best was their astonishment as I put on my sport coat, my shirt, my slacks, their faces shrinking back like I was acting in some kind of Dino de Laurentis Biblicla spectacle and they were the mob about to shriek "Unclean! Unclean!" and throw foam-rubber rocks at me.

Ring around the collar? A bad case of rotten-locker smell? An old kick-me sign still taped to my back from a high school study hall? No.

"It don't none of it match," Corporal Tolari explained.

"None of what?"

"The coat. The shirt. None of it. You got a brown coat on, right? But you got a blue shirt. And the grey pants. It don't match." There was also the problem of my standard two-and-seven-eighths-inch Brooks Brothers necktie, this being an era in which my barracks buddies got nervous if their ties got any wider than their shoelaces.

So I asked a stupid question. "Why don't brown and blue go together?"

"Cause one's brown and the other's blue. "

"So what?"

I could see it going through Tolan's mind: if brains were dynamite, this guy Allen wouldn't have enough to blow his nose. Clearly, I was dealing with a self-evident truth, here. Like the one that says you never wear white socks unless you're exercising. Or a striped shirt with a striped tie. Or you never button the bottom button of your vest. Or let leg flesh show between sock top and cuff. We hold these truths, and nobody knows why. If the world's greatest democracy can be built on this kind of thinking, why not men's fashion? On the Confucian Principle of Rectification of Names

In a 1977 issue of Gentlemen's Quarterly, subtitled "The Many Faces of You," (a frightening thought in itself) you can read about a guy named Tom Fallon, who works for a designer. Fallon says: "I don't spend a lot of time on clothes, and I don't much like to see men who are too perfectly dressed . . . I believe in the Seventies mixture of, say, an exquisite tweed jacket an $10 khaki trousers."

Sure enough, in a photograph, Fallon leans with cautious insouciance on his bicycle, clad just as he says, and shod in what appear to be middle-of-the-line, non-safety-toe surplus-store work boots, somewhere in the Georgia Giant range. Economically, ethnically, and functionally this rig is nonsense. Especially when you consider that "$10 khakis" have been replaced for years as work clothes by the stay-press, pre-crease jobs dyed in either that brown-green which is, I suspect, the precise color of the average trousers of the average customer of Sears or K-Mart or Montgomery Ward; or that grayed-out shiny blue that looks like the uniform for some other country's air force. But Tom Fallon looks terrific.

So did Woody Allen when he took Betty Ford, wife of the then-President, to a New York opening in tuxedo and sneakers. So does one Washington fashion doyenne whom I saw recently wearing those pinkish-clear-rimmed glasses you see on Yale and Harvard law professors - glasses which actually, in the 1930s, were dispensed by welfare agencies to the poor who wouldn't wear them out of shame, thereby making it possible for the rich to wear them out of modesty. And the doyenne to wear them out of whimsy.

This is the hiatus look. The hiatus look suggests that whatever one has been doing, one has just been called away from something else. One gains the panache of, say, a Ted Sorensen called off the squash court to arrive still sweating at Hyannisport to solve the latest Kennedy crisis. Hence the popularity of tennis clothes for one's Saturday shopping expeditions into Georgetown. Hence, the serious merchandising of a look which has you wearing sailing shoes, safari pants, and rugby shirt. The March, 1977, Gentlemen's Quarterly provides a list of fashionable footwear including construction boot, cowboy boot, hunting boot, motorcycle boot and ski boot. Never does the magazine suggest that these have any practical function, beyond providing the hiatus look. We may be stuck in the checkout line at Safeway, fiercely counting to see that everybody in front of us has the right to be in the ten-items-or-less line, but our hiatus look tells the world we just got off our trailer truck, horse, deer stand, Harley or expert's slope. Kurt Vonnegut once said that you are what you pretend to be. Despite the snappiness of this maxim, it never quiet works, in real life. Neither does the hiatus look.

One is tempted to blame this willful confusion on an industry whose best minds can run on about slub filament polyester fortrel expandomatic encron strialine. However, old China hands among us may diagnose it as a failure of the Confucian doctrine of the rectification of names. Said Confucius: if everyone acts, speaks, and dresses according to his title, be he official or farmer or whatever, society will be in order. Confucius was not concerned about "the many faces of you." Confucius would not have approved of the hiatus look, or of Tom Fallon wearing a British country squire's sport cost with a garbageman's shoes. No doubt Tom Fallon always speaks well of Confucius, however.

Unless he takes either the Maoist, Taoist or even Lin Piaoist lines, of course. Or a bit of all of them just tossed together! Here we're getting into the high fashion of the intellectual world, but why limit this to clothes? Imagine it! Wasn't old Hegel himself, with thesis battling antithesis, the father of the mix 'n' match concept? And what about that brezzy new go-anywhere look that only semiotics (all the rage in Paris) can give you . . .