As a teen-ager afflicted by a raging and nearly life-threating interest in sex, I happened upon a book called "Pornography and The Law." Ostensibly a serious treatise on the problem, it had the virtue of actually including some examples of the very pornography under discussion. I bought it.

Never mind some of the things I learned. What matters now is a chapter in which a social scientist was asked whether pornography sexually excited teen-agers. This is a variation of the old Is-the-Pope-Catholic? question, and so the answer, of course, was yes. But the social scientist listed some other things that do just as well. They included girls, riding on trains, getting up in the morning, walking and almost anything you can name. To a teen-age boy, all life is a sexual stimulant.

Now once again the law is taking a hard look at pornography and about to issue yet another report. This one, reportedly gamier than the one I bought as a kid, finds a "causal link" between pornography and violence. The conclusion, more a wish than a scientific finding, was a foregone conclusion. The panel was chosen by Attorney General Edwin Meese and includes persons whose preconceived anti-pornography views have long been known. It's a wonder they did not find a "causal link" between pornography and the farm crisis.

Still, let us assume that there is a link between pornography and violence. Let us make that assumption even though most social scientists do not and a previous presidential commission has found otherwise. Let us assume, in fact, that the social scientist of my memory, the one from "Pornography and the Law," is once again testifying before Congress and concedes a "causal link." What else might he say?

Well, for starters, he might say that the same link exists between television and violence, movies and violence, and music and violence. He might point out that there is as much sexually oriented violence toward women in afternoon soap operas as there is in pornographic movies, and he might further point out that in much pornography there is no violence at all. Certainly, if violence is our concern, there ought to be a presidential commission to study Sylvester Stallone.

But the social scientist should not stop there. He should say that the term "causal link" is claptrap, an admission that hard evidence is lacking and, more than that, the sort of opportunistic reasoning that governments have employed in the past to justify the urge to censor. After all, if a causal link to violence is what we are seeking then it may exist in areas having nothing to do with sex. It might exist in the political sphere as well, beginning with the Declaration of Independence. It is nothing less than a call to revolution, and if that isn't violence then nothing is.

But why stop there? We could include, also, Tom Paine's writings, which were radical even to radicals. How about the writings and speeches of American abolitionists such as William Lloyd Garrison, which preceded that bit of violence called the Civil War? Let's include the speeches and the pamphlets of union organizers and, much more recently, the utterance and writings of both civil rights and anti-war activists -- and (just for Meese) some of the speeches and writings of the antiabortion movement. All these movements have been accompanied by violence.

Indeed, it would be hard to draw the line. Fortunately, though, it has already been done. That bit of writing is called the First Amendment and, according to it, it is immaterial whether anyone alleges a "causal link" between the written word (or, by extension, film) and violence. You could argue that there is a world of difference between "Debbie Does Dallas" and some political tract, and indeed there is. The differences have to do with substance, intent, purpose -- a whole range of things. But what they now purportedly have in common is the fatuous reasoning that if violence is a result, then the government has an obligation to do something. Censorship comes to mind.

Over the years, the American judicial system has tried to distinguish between speech or writing and their sometimes violent consequences. The Meese Commission has trampled right over that distinction. Commission members might say that it is just stating facts and not calling for censorship, but its methodology and attitudes say otherwise. You know what they want from what they write. As they would say, there is a "causal link."