Feed a fact to Marvin Harris, the Columbia anthropologist, and watch the ideas jump like electric sparks, making one startling connection after another.

In a single breath, he links feminist activism to the emergence of gays from the closet to crime in the streets.

For him, the connections are obvious. He's writing a book about it.

When the women take jobs -- any jobs, dead-end jobs, drudgery jobs -- what happens? First, he says, unionization is delayed, since many of these jobs are clerical, and "clerical workers are now the predominant work force in the U.S." Next, with 35 million women moving into the work force, unemployment among young males skyrockets. And unemployment is tied to crime.

"I tell women there's a relation between terror in the streets and women in the offices, and they don't see it," says Harris.

"People thought feminism started in the early 1970s and was inspired by the civil rights movement," he says. "But the call for women to leave the home and enter the job market came much earlier. By 1965 there were already 25 million housewives in the labor market."

Harris, a 52-year-old author and lecturer who is something of a storm center in his field, was in town for a Smithsonian address on his "cultural materialism."

He was a little nervous. His notes appeared to consist of a page of scrawled words with boxes drawn around them and arrows between the boxes. His large head lunged forward as he made a point, and his somewhat heavy frame made a busy shadow as he applied body English to his argument.

One suspected that he was happier in his study or the classroom. There were too many ideas, and he wanted to get them all out, but first he had to explain the concepts that spawned them . . . He took longer to warm up than Pavarotti.

When at least he got onto home ground -- specifics -- the ideas came tumbling out.

Harris worries that we are all but unaware of the colossal events of our time.

"Here we have a fundamental change in the American family, the collapse of the pro-natal (or more babies is better) policy. And it's not being perceived. We're not geared to comprehending structural changes in our culture. We must apply to our social life the comprehension we apply to technology. We've got to be as objective about our lives as we are about the temperature of Jupiter."

Why did women flock to the labor market? For Harris, the answer lies in the need to intensify production. From his 1977 book "Cannibals and Kings." t

Intensification -- the investment of more soil, water, minerals, or energy per unit of time or area -- is in turn a recurrent response to threats against living standards . . .

In this case, inflation forced families to send the wife to work and stop having children -- in order simply to maintain their standards of living.

"You can't establish a minimum level of calories, or proteins, or shelter or air or whatever," Harris says, "and expect people to cut back to them. Once a level is achieved, even if it's far above mere subsistence, if you have to make any cuts, people start making a fuss."

The women go to work. Baby production slacks off. And government policy eases its former support of population increase "because the benefits of this untapped reservoir of cheap, docile labor overshadow the long-range benefits of population increase."

As the society and the government itself turn from pro-natal to anti-natal attitudes, marking the end of "many centuries of the procreative and marital imperative," the attitudes toward homosexuality and nonprocreative sex change too, he says.

"Black always had those patterns, since the turn of the century. It was not liberation, it was that the women had to go to work to help support the family because the men couldn't get good enough jobs. Many of the sexual patterns now being touted as liberation of women -- having a job, being independent, having children alone -- were characteristic of blacks for some time. It's another example of our failure to comprehend what's happening."

Just as the family will work harder to maintain its status, so the culture itself will intensify production to stay at its present technological level, Harris explains. That means oil. The more we depend on oil to maintain our standard of living, the more intensely we pursue it, even to the point of risking global holocaust in a Persian Gulf confrontation.

Food production, to take the most critical example, has now become totally dependent on our oil supply. Agricultural traction, lifting, hauling, and transport were captured first. Now we have reached the stage where the conditioning of the soil through chemical fertilizers and the defense of plants through herbicides, pesticides, insecticides and fungicides have also become totally dependent on an ever-increasing supply of petrochemicals. The so-called "green revolution" is an oil revolution. . . .

It now takes 22,000 calories of energy, Harris adds, to produce 270 calories' worth of beef.

"Why is beef so important to Americans?" Harris relates it to the expanding frontier, the westward move of the corn belt, the superiority of cattle to pigs as range animals. He has written at length on the role of animal protein in history, the universal quest for it, its part in the relation between cannibalism and war, its connection with religious phenomena from communion wafers to sacred cows.

A teacher at Columbia since 1953, Harris headed the anthropology department for three years. He lectured extensively at American universities, and has written several books, including one called "Cows, Pigs, Wars and Witches."

Probably Harris' most controversial notion is the cost-benefit theme and its determinist implication. Why do Indian peasants continue to have large families? "On a farm, the costs are less, the food is there, and children are set to work very young and later will support the parents," he says. So the cost-benefit ratio is favorable.

But in our culture, where studies show it costs $50,000 to $100,000 to rear a child to age 18, not counting college, the cost-benefit is prohibitive. So the birthrate continues to drop.

I do not deny that the intangibles, such as the joy of watching children grow up, also influence behavior. But who is to say that the joy of watching 10 children grow up to be carhops is greater than the joy of watching one grow up to be a surgeon? Or that it is more rewarding for a woman to rear one surgeon than to be one herself and rear none?

Of course, if you tell people who are forgoing children or delaying marriage that they are just following the cost-benefit pattern, they resent it.

"It's another instance of how the systemic level is obscured by people who don't want to see the truth. We have things in our social lives we don't want to know. If we are rich, we don't want to know that this relates to the poverty of others. We don't want to face up to our part of the responsibility for crime in the streets. We prefer to say those individuals are acting under some evil principle that we're not contributing to.

"The mystifiation of social life arises for the inequalities of social life.

Men didn't want to see that they dominated and exploited women they said no, that's woman's nature. It only changed when it became more convenient to them to have women work."

Harris, who is married and has two children, thinks that taking a systemic view of things would cut the divorce rate because working couples would realize that their tensions and conflicts are not just problems that arise from themselves.

And the Me Generation people wouldn't have to feel bad because they think about themselves all the time.

"The reason why they only worry about themselves is that they only have themselves to worry about. Because they're not rearing a family.One thing about having children is that is does make you concerned for the future."