THE FIRST BIG televised all-in Democratic debate of the 1988 season, conducted in Houston by William F. Buckley Jr., was an unexpectedly enjoyable event. Buckley's air of pained amusement as he listened to what he must have thought was Bolshevik nonsense gave added texture to the proceedings and also gave several of the seven a chance to exhibit presence of mind and a flair for riposte.

They debated Buckey rather than one another, but that worked in their favor. Buckley superciliously inquired of Rep. Richard Gephardt of Missouri how it could be "darker than midnight," which is how Gephardt described the state of affairs under Reaganomics. Gephardt shot back, "Under Reagan it could."

When Buckley took exception to Massachusetts Gov. Michael S. Dukakis' description of the contra war as "illegal", Dukakis fired back with a heavily applauded statement that "they," meaning Buckley's idolizedadministration, "don't respect the law, they don't respect the Constitution."

Sen. Albert Gore Jr. of Tennessee scored when Buckley offered a counter-opinion on the feasibility of "Star Wars" from a panel opposing Gore's views. Gore replied hardily that Buckley's experts were known partisans, and Buckley backed off.

None of the candidates blundered or lost his cool. Nor did they depart from each other in their denunciations of Star Wars and contras -- although curiously no one brought up the most urgent issue, the reflagging of ships in the Persian Gulf.

Sen. Joseph R. Biden of Delaware, who is sometimes thought to be too hot, was mellow and reasonable and even at one point said, "It wasn't all Reagan's fault." He also defended the Rev. Jesse Jackson from Buckley's baiting about a toast to Castro that Jackson had once offered. "Jackson brought somebody home," said Biden equably.

Paul Simon was civil and reasonable throughout.

None of them, alas, is a wit. In one segment the candidates offered filmed excerpts from campaign appearances which they presumably thought presented them at their best. All of them told stories of varying degrees of infelicity.

This early, the two hours mean most to campaign managers and coaches who can use the videotapes as training films, looking for correctable flaws. Dukakis talks through his nose and drops his final g's; Bruce Babbitt shouts as if standing in a high wind with the sheriff about to close in; Gore in his formal statements tends to be windy and pompous; Jackson's handlers may be happy to see that a severely constrained format serves him fairly well. With a two-minute limit, he sounds much less threatening.

Perhaps the most interesting thing about the encounter was the audience. It was amazingly responsive and liberal. The most unscrupulous and resourceful candidate-promoters could hardly have flown or bused in that many enthusiasts from Massachusetts or other centers of dangerous secular humanism. Or has Houston become a left-wing hotbed while no one was looking?

The earliest indication of its temper came during the first statements of the seven. Biden was stopped cold by applause when he rapped Star Wars. Jackson, raising the question of the possible impeachment of the president, got a big hand. They loved it when Simon said we should be sending Peace Corps volunteers instead of guns into Central America.

If Houston is any measure, the Democratic Party is not a party that is searching for a centrist or a pseudo-Republican. They sounded like people who know exactly what they don't want.

Curiously enough, there was no discussion about the issue that at the moment most united the party and the candidates: the nomination of Robert H. Bork. Before the curtain went up in Houston, the cry went up in Washington about his unacceptability. Anyone in Houston who had counseled a little patience and study of the record might have been booed.

The nomination, of course, gives Biden, as chairman of the Judiciary Committee, a big leg up on the others. If he handles this well, he could become the darling of the kind of people who determine nominations, namely the activist left.

The tone of the coming debate was set in extreme terms by Sen. Edward M. Kennedy of Massachusetts. Said he on the Senate floor:

"He (the president) should not be able to reach out from the muck of Irangate, reach into the muck of Watergate and impose his reactionary vision of the Constitution on the Supreme Court and on the next generation of Americans. No justice would be better than this injustice."

These are strong words, perhaps intended to force the pace on Biden.

Maybe all the participants will carry around in their heads for the next seven months the applause they heard in Houston. It didn't tell them much about who Democrats want, but it did tell them what they don't want.

Mary McGrory is a Washington Post columnist.