SCIENCE fiction movies often provide clues to the present as well as the future. During the 1980s, for instance, many sci-fi pictures - such as ``The Brother From Another Planet'' and ``Alien Nation'' - dealt with racial issues, showing an increased awareness of such matters in American society. The latest trend to crop up in futuristic films is a changing attitude toward science itself. Movies as different as ``Robocop 2'' and the new ``Flatliners'' take a highly skeptical view of science and technology, suggesting that high-tech approaches to human problems have limits as well as possibilities.
The heroes of ``Flatliners'' are medical students with a weird project that no professor assigned them: One member of their group will deliberately die, ``explore'' the afterlife for a few minutes, then be resuscitated by the others.
One by one, each student undergoes a ``killing,'' has some kind of murky adventure, and returns to tell about it. Then strange experiences start happening to the ``explorers'' in this life, and all their IQs combined aren't enough to figure out what's going on.
Even in movie terms, this story doesn't make much sense. If intellectual curiosity were their motivation, the students could satisfy it more safely - and reliably - by interviewing people who have undergone temporary ``death'' without going out and looking for it.
The plot becomes even more ridiculous in the second half, when the heroes find they are being haunted by people they once did something mean to - usually friends from elementary school, who may or may not be deceased themselves. The movie seems to be attempting a traditional ``morality lesson'' here, suggesting that thoughtlessness today might bring a penalty in the future.
Unfortunately, the film carries this to ludicrous extremes, resolving the tension in a climax that's as sappy as it is contrived.
Apart from the silliness of its story, ``Flatliners'' is smartly enough directed (by Joel Sch"umacher) and delivers enough summer-blockbuster thrills to be a strong candidate for box-office success. Indeed, no other Hollywood movie of the season holds as many jolts and surprises; and those commodities sell especially well at this time of year.
This potential for popularity is what makes the picture's attitudes worth noting: Millions of people will eventually hear its message, and that message is one of extreme skepticism toward the scientific ideas held by the main characters. At the beginning of the story, they clearly believe they can do anything - even blur the line between life and death - with the high technology at their disposal. What they learn is the amazingly old-fashioned idea that science is limited by the intelligence and morality of the people who wield it. Although nobody actually says it, you can almost hear the classic line that worked its way into so many ancient Hollywood movies: ``There are some things mankind wasn't meant to tamper with!''
``Robocop 2,'' one of the summer's earlier science-fiction offerings, takes a similarly dim view of high-tech solutions to human problems. As in the original ``Robocop,'' the hero is a police officer whose mind has been transplanted to a ``bionic'' body full of wires and computer chips. This makes him the perfect action-movie hero: part man, part machine, and all macho.
It turns out that ``Robocop 2'' is not only the title of his new movie, however, but also the name of his worst new enemy - an imitation robocop who's inhuman even where he's supposed to be human, since his brain comes from a drug-addicted criminal.
The first ``Robocop'' movie had a couple of virtues. As the title character, Peter Weller did a good job of combining human complexity with tough-guy virility, and there were neat touches of social satire. The makers of ``Robocop 2'' aim for the same qualities, including satirical bite. In the story, an ambitious scientist - a psychologist who puts research ahead of people - starts tinkering with Robocop's computer programs, on the theory that our hero shouldn't just capture and shoot criminals, but talk to them about their problems.
After spending a little while as a Robowimp, he gets his tough-guy instincts back in time to deal with the villain, Robocop No. 2, and save the city of Detroit while he's at it. But not before he's illustrated the movie's notion that science doesn't have the ability to make human or thinking machines, even if it can make mean ones.
The film also paints a somber portrait of Robocop's basic existence, suggesting that loneliness and lovelessness are also problems that technology can't begin to deal with.
Other recent science-fiction films also treat science in an unromantic way. ``The Handmaid's Tale,'' directed by Volker Schlondorff and based on Margaret Atwood's somewhat more exciting novel, depicts a future America in which all science - indeed, all rational thought - has been defeated by religious fanaticism.
``Back to the Future Part III,'' directed by Robert Zemeckis, transports its time-traveling heroes to the Old West, where they have a conspicuously low-tech adventure full of horses and old-fashioned plot twists. This reflects the continuing influence of ``Star Wars,'' which adapted western-movie clich'es to a space-age setting, and showed its own skepticism toward the ultimate usefulness of science by setting up ``the Force'' as a higher, less materialistic power.
Future movies may revert to the science-worship of such bygone epics as, say, ``When Worlds Collide'' or ``Fantastic Voyage,'' but for now the message is different: There are some things mankind was not meant to tamper with, and scientists who try may be in for a dramatic letdown.