There are zanies in the woodpile. There are zanies dancing on the lawn. There are zanies living beneath the wallpaper. America is overrun with zanies, with Zaniness Unbound, with double-digit drollery, and there are no sights of comic relief in sight.

Robin Williams, the Frank Lloyd Wright of Nutsy Cuckoo, speaks of Comedy Hell and Comedy Heaven. Perhaps we are living now in Comedy Purgatory. Laughter may be good for the soul, but how much can a single soul take? Laughter may be the best medicine, but that doesn't mean you can't o.d.

There is too much comedy and not enough happiness. This may get worse before it gets better.

It's been said no single program form dominates prime-time TV this season, but if you look even half-closely, you will see the zanies are everywhere; it doesn't take a Joe McCarthy to find them. There's a zany Japanese cook on "The Last Resort," a pair of zany bumbling brothers on "Working Stiffs," a pair of kookie cutups on "California Fever," even a resident wiseacre on $240-Robert."

On "The Misadventures of Sheriff Lobo," a fat and daffy deputy named Perkins does funny things like drive his cop car into lagoons and get his pants bit off by Dobermans. On the returning "Dukes of Hazzard," a crackerbilly sheriff named Rosco Coltrane drives his car into lagoons, too, though it isn't certain whether dogs have eaten his pants yet.

But television is subject to fits at all times of day, which is why the revamped daytime Dinah Shore talk show has been promoted to local stations as offering "Enterfunnyment," obviously just what the world needs.

The hugh successes of funnybone-breakers like "Saturday Night Live" and the movie "National Lampoon's Animal House" helped create a new generation of what we might call folk comedians. They're the kids who probably would have become folk singers in the '60s; they would have expressed themselves then through plaintive laments.

No one is buying plaintive any more. In city after city, clubs styled after the famous Comedy Store and improvisation in Los Angeles are springing up so young zanies can set forth silly, apolitical grievances in cominc terms for peer-group audiences to cheer and applaud.

Where onece one might have avoided a nigh spot for fear of running into a local version of The New Christy Minstrels or the syrupy Up With People singers, one now avoids the same bistro for fear of running into the local version of the Not Ready for Prime-Time Players. Rock music is nosediving in popularity, but nutty, zany, gang comedy is thriving everywhere.

In addition, a dozen top talent agencies and production houses in Hollywood have set up special comedy departments for TV and film projects. It is all but impossible now to get turned down with a comedy script by a movie studio, which is why such witless wonders as "The Villain," "Americathon" and "Hot Stuff" didn't get ix-nayed at the rough-draft stage by someone in full possession of his faculties.

Cable television outfits like Time-Life's profitable Home Box Office are feverishly trying to develop not only their own versions of network sitcoms. HBO has had success with comedy concert specials by Robin Williams and Lily Tomlin and with such cheerfully smutty hours as National Lampoon's "Disco Beaver from Outer Space," which featured a campy vampire named Dragula who only bit limp wrists.

Gang comedy has grown increasingly popular on television because it is easier to make six semi-talented people seem amusing than it is to make a single semi-talented person seem amusing. Syndicated shows like "Madhouse Brigade" and "Second City Television" cross the impish irreverence of "Saturday Night Live" with the zippy-dippy pace of Monty Python. Very often, they fail miserably.

And therein, indeedy-do, lies the problem. In any civilization, only a limited number of people have the capacity to be genuinely funny at a given moment. The problem now is we are being given too many moments. Sadly, too, a lot of this whacky, zany, essentially mindless comedy is being lapped up by members of a generation who don't really know what's funny.

They don't know what music is, because they were brought up on rock and roll. They don't know what humor is, because they were brought up on "The Partridge Family" and "The Brady Bunch" and other programs in which laughter was prompted not by the wit of writers but by the transistors and capacitors of the canned laughter machine.

We are living in the age of the devalued laugh. One can understand a society seeking refuge from pain and strife in escapist froth. But at some point the lust for yocks and titters, and the entertainment industry's eagerness to appease that lust, gets a little pathological. Our incredible surplus of comedy suggests that seldom have so many people been so desperate for so much escape.

What's next -- terrorist repertory companies roaming the streets with whoopee cushions? Door-to-door free-lance zanies filling the few remaining laughless moments in the American day? There comes a time when comedy turns to tragicomedy all by itself. There comes a time when the music of our laughter becomes shrill random noise.

There comes a time when stand-up comedians should sit down.