Religion and science are butting heads again over the case of a science writer who doesn't believe in Darwin's theory of evolution and a leading science magazine that, as a consequence, doesn't believe he ought to be published in its pages.

The freelance writer, Forrest Mims III, was on the verge of becoming Scientific American's regular "Amateur Scientist" columnist a year ago, he says, when he divulged to editor Jonathan Piel that he subscribed to the so-called creationist theory -- a belief, rooted in Christian scripture, that ascribes the origin of life forms to acts of creation by God.

Fearing that publicity about Mims's unorthodox views might embarrass the magazine, Piel canceled plans to make Mims a regular contributor. Last fall, after protracted negotiations, Scientific American undertook to publish three columns Mims had prepared, with no further obligations, and Mims signed a waiver of his right to sue the magazine.

Now that the columns have appeared, Mims has been paid for them, and the magazine has refused to consider publishing any other work by him, the 47-year-old Texan is pressing his claim that he was rejected because of his religion. He describes himself as an evangelical Christian.

The Texas affiliate of the American Civil Liberties Union has weighed in with a letter to Scientific American on Mims's behalf. Comparing the writer's treatment to 1950s blacklisting, acting director Lamar Hankins wrote, "In a country founded on religious pluralism your action seems out of place and grounded in the intolerance of another era, if not another century."

But even more important to Mims was the boost he got this week from the American Association for the Advancement of Science, which he had petitioned for an opinion.

In a letter from Sheldon Krimsky, chair of the AAAS committee on scientific freedom and responsibility, Mims -- and indirectly Scientific American -- was told that "even if a person holds religiously-derived beliefs that conflict with views commonly held in the scientific community, those beliefs should not influence decisions about publication of scientific articles unless the beliefs are reflected in the articles." The committee refused to address the specifics of Mims's dispute with Scientific American.

After receiving the letter, Mims said, "I'm sure that most of the {AAAS} members may not share my personal views. But they are not living in the dark ages. Scientific American's editor is living in the dark ages. He's practicing what was practiced at the time of the Inquisition, judging people for their beliefs and not what they can do."

Piel has made no public comment on the case except to say that Mims's religious views had nothing to do with the magazine's decision. A letter to Mims from Scientific American's lawyers Monday reiterated that the venerable publication "has never discriminated against anyone for religious or any other reasons." In a brief telephone conversation, Piel said that the AAAS statement's description of "criteria for publishing scientific literature is 100 percent correct, and I subscribe to it."

Though he would not elaborate, another passage from the lawyers' letter sheds light on the editor's reasoning in the Mims case: "What you characterize as 'religious discrimination' was merely the expressed concern of {Piel} that association of the magazine's name with your views concerning evolution could harm the cause of science and alienate crucial groups of authors or readers."

Put more succinctly, as Piel did in an autumn telephone conversation that Mims surreptitiously recorded, "There's no question that on their own merits the columns are fabulous. ... I trust you. You're a man of honor and integrity. ... It's the public relations nightmare that's keeping me awake."

The nightmare, according to sources at the German-owned monthly, was that creationist groups might point to Mims's position at Scientific American as evidence of their theory's legitimacy. In any case, the public relations nightmare that Piel was seeking to avoid is now upon him, thanks to an aggrieved and aggressive Mims, who has peppered the news media with his claim of religious discrimination.

Many scientists assert it is not Mims's religious views that are at issue, but his scientific ones. The rub, of course, is that for Mims and other creationists they are one and the same.

"If he believes in creationism, he has established that he doesn't have credibility to write about science," said Robert Park, a physicist at the University of Maryland and head of the Washington office of the American Physical Society. "Creationism can be judged on scientific grounds and this guy has judged wrong."

Others queried on the subject said that Mims's belief in creationism indicated crippling flaws in his thinking, no matter what subject he might address. "We're talking about a process here," said Jon Franklin, a Pulitzer Prize-winning science writer now on the faculty of the University of Oregon. "If a person believes in ESP, then I have some questions about that person's ability to think about psychology."

Mims begs to differ. He says all his writings -- he has written hundreds of articles and 70 books, he says -- stand up to conventional rules of scientific evidence and reasoning, and should. His writing for the "Amateur Scientist," a column on building gadgets and conducting home experiments, would have been no different, he said. "Let them judge my writings on their content and not on what I do on Sunday," Mims said.

Nonetheless, Mims said, he had sought to assure Piel that he would not use the "Amateur Scientist" column as a forum for his religious views. New York University's Dorothy Nelkin, author of "The Creation Controversy," was skeptical of any such claim. She said creationists "have a history of trying to penetrate mainline scientific organizations ... they do tend to play the legitimacy game like people in any social movement do." This strategy, said Nelkin, has generated "paranoia in the scientific community, which is reflected in Piel not wanting this guy on the staff."

At least since he's been battling to reverse Scientific American's decision, Mims has not been shy about defending his views about the origin of life. In an interview he declared that "much of what is written about evolution is not testable, just as much of what is written about creation is not testable." Referring to the National Museum of Natural History in Washington, he said, "Go look at the fossils for yourself. That's how I became a creationist. I didn't become a creationist by going to church."

Even so, Tim Appenzeller, a Scientific American editor when the dispute began, said he never regarded Mims as a Trojan horse for the creationist movement. "I don't think he was trying to get his foot in the door and then promote anti-science, which is what I think creation science is."

Appenzeller, now a senior editor of The Sciences cq/to magazine, said there was nothing in Mims's background or his written work to suggest a proselytizer for creationism.

In fact, it was only when Mims flew from his home town of Seguin, Tex., to the magazine's New York offices last August to discuss his plans for the column that his views became known to his prospective editors. Mims said he and Piel were having a "cordial" and "pleasant" conversation -- Piel was "bubbling with enthusiasm" about the column, he said, and told him "we should have snapped you up years ago" -- when the editor asked about other publications to which he contributed.

When Mims mentioned (after a long list of scientific journals) a few Christian publications, Mims recalled, Piel asked him: About what? Bicycling, Mims replied. Then Piel asked him point-blank whether he subscribed to the Darwinian theory of evolution. When Mims said he did not, he recalled, the complexion of the conversation changed dramatically.

By the time he left Scientific American that afternoon, the deal appeared to be on ice. The three-column agreement last fall, and the clearest indications that Scientific American would publish nothing more by Mims, sealed that reversal of the writer's professional fortune -- and the sudden death of "my lifelong ambition," Mims says.

Authorship of "The Amateur Scientist" has a quality of destiny for Mims, who maintained that its longtime author C.L. Stong "told me before his death that some day I would be writing the column." Nearly a year after he and the magazine formally settled their dispute, Mims said he clings to the hope that the magazine can be embarrassed into relenting. It is an unlikely scenario.

Still, he has supporters inside the scientific community who see ominous signs in his treatment by one of science's leading popular organs.

Krimsky, the Tufts University professor who chaired the AAAS committee, said in an interview, "The criteria to be used in evaluating someone's work should be what's in his work -- not on the man and his complex life and thoughts, both personal and scientific. ... We have a long history and tradition of scientists who have divided their personal beliefs and their scientific beliefs. Galileo was one of them. So was Newton."