THE SECRET MUSEUM Pornography in Modern Culture By Walter Kendrick Viking. 288 pp. $18.95

THE SECRET MUSEUM by Walter Kendrick is a thorough, scholarly history of pornography, almost entirely free from polemic. Its tone of ironic detachment, however, does not ultimately conceal its message: that since all efforts to legislate against pornography have been self-defeating, we should have the sense to avoid waging any more of these "ignorant battles."

Kendrick devotes much of his book to famous obscenity trials (from Baudelaire to Henry Miller), emphasizing the foolishness of trying to control the uncontrollable via inappropriate means. Law courts, after all, are designed to penalize criminals and compensate their victims; yet the crime of publishing pornography has never been conclusively defined, and no victim has ever been found -- by which I mean that we have yet to see a plaintiff claiming damages from a pornographer for having been depraved and corrupted. Judges have had to make the best of the situation by trying to imagine whether erotica would be liable to injure a hypothetical "average citizen," and laws against pornography have been enacted not because it has been proved harmful but because moral crusaders have feared that it might be.

The Secret Museum traces this suppressive impulse back to the discovery of erotic art in excavations of Pompeii in the 1700s. Shocked by depictions of the god Priapus, whose enormous penis was originally intended merely as a fertility symbol, museum curators placed such items in locked rooms -- a "secret museum" that was off-limits to the general public.

The invention of the printing press and the spread of literacy demolished this museum's walls. Kendrick argues that the description of sex with purely salacious intent, subsequent attempts to control such descriptions, and the word "pornography" as we now understand it, all originated after 1800. Historically, therefore, pornography is a relatively recent idea.

The fear that fiction might harm its audience is not recent at all, however. Plato proposed to ban poets from his Republic lest they distort the truth, and Socrates argued that an audience might be tempted to emulate unseemly behavior of characters in a play. By contrast, Aristotle claimed that fiction provides catharsis, purging rather than corrupting its audience. Centuries later, opponents and proponents of pornography adopted similar positions in a debate that Kendrick describes as "permanently inconclusive."

But is it? The 1968 U.S. Commission on Pornography and Obscenity attempted to settle the matter by sponsoring psychiatric evaluations of volunteers before and after long-term, intensive exposure to erotica. Far from becoming depraved, they became bored, and the commission concluded that pornography had no damaging effects whatsoever. President Richard Nixon rejected this finding when the report was delivered to him in 1970; for if it were true, "it must also be true that great books, great paintings, and great plays have no ennobling effect on a man's conduct." To this, Kendrick responds that "history provides no proof that 'great' representations have had any such effect on anyone's actual behavior." He seems to believe not only that pornography is harmless, but that all artistic works are incapable of subverting us. It is absurd, he says, that "suppression of the image can prevent perpetration of the deed."

UNFORTUNATELY, he offers no evidence for this opinion, and I am not entirely persuaded by it. True, most studies have failed to prove a causal link between the images we see and the deeds we do; but this is partly because of the difficulty in controlling all the variables involved. Anecdotal cases are plentiful: Charles Manson, for example, modeled his cult on the science-fiction novel Stranger in a Strange Land, in which a messianic figure gathers glamorous female disciples, preaches free love, and murders establishment figures who try to stop him (this according to Ed Sanders' excellent account, The Family). Manson even named his child after the protagonist in the novel.

Speaking personally, as a writer of fiction, I have occasionally been told that my work has somehow changed a reader's life. And as a reader I testify to my own "corruption" by pornography upon arriving in New York in 1970. By my standards, I was all the better for discarding repressive values acquired during a British childhood; but by conservative moral standards I was surely corrupted, to the point where I not only became a consumer of erotica but started writing it myself.

Kendrick's refusal to admit any social impact of pornography seems an evasion, as is his dismissal of Andrea Dworkin's claim that by portraying women as victims, pornography discriminates against them. He never seriously examines her case, even though casual inspection of any news stand confirms that she is correct: much modern pornography indulges freely in "acts of violence against women."

In response to her attempts to redress the matter via civil-rights legislation, Kendrick reiterates his basic argument: that all attempts to control pornography have been historically futile, and it has flourished "in direct proportion to the energy of its combatants." His thesis, however, rests entirely on cases in Britain, France, and the United States. One need only look at more authoritarian regimes to see that suppression of any form of literature occurs with a high degree of success if the state is granted sufficient power. The question is not whether suppression is possible but whether Americans would tolerate the methods required to achieve it.

In a country that has enjoyed Prohibition and McCarthyism, a similar witch-hunt directed at smut seems at least a remote possibility, at which point the civilized courtroom debates that Kendrick ridicules so eloquently would become irrelevant. Judges do not make law, they merely interpret it. Pornography could surely be suppressed by some new act of Congress in coordination with televised proceedings of an investigative committee and help from the Internal Revenue Service.

Enumerating the past follies of jurists and zealots, in the hope that we may learn from history, is a very well-mannered way of arguing against censorship, and The Secret Museum is an endearingly gentle book. One wishes, however, that it had taken a slightly more aggressive attitude toward the fundamental issue of whether any kind of restriction on freedom of speech is tolerable, regardless of the possible impact of that freedom on male consumers, teenagers, or battered wives, in a society that claims individual liberty as one of its fundamental goals. ::

Charles Platt's most recent books include "Dream Makers: Science Fiction and Fantasy Writers at Work" and "How to be a Happy Cat."