A lot of black youngsters see Spike Lee as a teacher. There are his films -- particularly, of course, the resurrection of Malcolm X. There is also his "attitude." For white interviewers -- in television or in print -- a conversation with Mr. Lee is often a minefield. He seldom lets the interviewer forget which color he is not.

As a teacher, Lee had this to say in the Nov. 12 Rolling Stone: "A lot of people will have to do a lot of explaining on AIDS one day. All of a sudden, a disease appears out of nowhere that nobody has a cure for, and it's specifically targeted at gays and minorities {i.e., Hispanics and blacks}. The mystery disease, yeah, about as mysterious as genocide.

"I'm convinced AIDS is a government-engineered disease. They got one thing wrong, they never realized it couldn't just be contained to the groups it was intended to wipe out. So, now it's a national priority. Exactly like drugs became when they escaped the urban centers into white suburbia."

Spike Lee is hardly the originator of this theory of the ultimate racist pogrom. For years it has been promulgated, usually without rebuttal, on some black radio stations. Nor is itlimited to obsessive autodidacts. As Clarence Page of the Chicago Tribune said last year:

"You could call conspiracy theories about AIDS and drugs fringe ideas, but they seem to have a large following among the black intelligentsia. And it's present at the grass roots too."

John Singleton, whose first film was the much and justly admired "Boyz 'N the Hood," has told the New York Times: "If AIDS was a natural disease, it would have been around 1,000 years ago. I think it was made in order to kill undesirables. That would include homosexuals, intravenous drug users and blacks."

Then there are those who find more specific creators of the plague than "the government." Steve Cokely, a Chicago "activist," lectures from time to time at colleges at the invitation of some black student groups. He has said that Jewish doctors inject the AIDS virus into blackbabies {Chicago Tribune, May 2, 1988}.

All of this is speech protected by the First Amendment, which does not restrict its shield to only truthful communication. To counter the effects of such speech, it might be useful to try that vintage remedy for poisonous expression -- more speech that tells it like it really is.

But who will speak truth to Spike Lee, John Singleton and a good many others? Some years ago, when Louis Farrakhan began to be practically a household word, a number of Jewish leaders asked their black counterparts to say something -- out loud -- about Farrakhan's antisemitism. The response from some black religious and secular figures was that they did not consider it necessary to continually reaffirm their own lack of bigotry every time a black speaker said something that offended Jews.

The late Nathan Perlmutter -- then national director of the Anti-Defamation League of B'nai B'rith -- told me at the time that he thought those requests from Jewish leaders were demeaning. "Why should we ask anyone to go against Farrakhan but ourselves?"

I went with Nate, as he was usually called, to a session at Columbia University attended by black journalists and students. From some in the audience, conspiracy theories about Jews became a thickening obligato as the evening went on. Perlmutter -- with good humor and utterly clear facts -- cut through them all. He had no idea if he had illuminated any minds, but he was glad he came. Perlmutter was a passionate defender of free speech, including that of the conspiracy spinners. "Boychik," he would say, "what's the alternative?"

If such distracting, energy-wasting conspiracy theories as those of Spike Lee and others are to be dealt with, there ought to be public dissections of those theories. As Louis Brandeis said: "Sunlight is the best disinfectant."

If Bill Cosby -- who once seemed to have some vague sympathy with the notion of a conspiracy to create and spread AIDS -- has abandoned that myth, he could be an effective teacher, through television and videos in schools, about the actual nature of AIDS. After all, he has a doctorate in education from the University of Massachusetts.

Other demystifying black figures -- from the academy, from films, from sports -- could be of great help in ridding minds, young and old, of these malignant conspiracy tales. Otherwise, once hooked on this way of imagining evil empires, some people make it a vocation, which hardly does them or anybody else any good.

As for Spike Lee, does he plan to provide any evidence that "AIDS is a government-engineered disease"? Or maybe his sources are extraterrestrial.