THE RADCLIFFE Institute sits in Radcliffe Yard, and yet surprisingly few Cliffies know anything about it. Mrs. Mary I. Bunting, president of Radcliffe, hasn't publicized it very well, considering her great interest.

The Institute caters to women who somehow have held on to big ambitions, even though they have often already achieved husbands and babies. They seem to be preserved Cliffies, or perhaps preserved freshman Cliffies--because they seem so unresigned.

But the women at the Institute are different from the rest of us Cliffies since they have stuck it out. We don't know if we will. Within a few years, we may store our books in the attic and start studying china patterns. The members of the Institute, however, ranging form 25 to 60 years old, have remained ambitious.

When I first visited the Institute in March, I wondered what kind of woman remains ambitious about careers, when so many women do not, and when it perfectly acceptable to give up career plans as if they had been adolescent daydreams.

These Institute Scholars, known officially as Associate Scholars, are awarded fellowships of up to $3000 per year to work on independent projects on a part-time basis. Chosen from more than 200 applicants, 18 to 25 women, about half of whom have doctorate degrees, become Institute Scholars each year. The Institute can accommodate only 40 Scholars at any given time, so a Scholar can stay at the Institute two years at the most.

The projects very greatly: one Scholar is studying the use of dance therapy for psychological and physical rehabilitation; another, how to communicate physics to children and laymen; another is writing the music and libretto for an opera; and another is exploring pre-Euclidian mathematical sources.

The Scholars also very greatly in their daily schedules. Each has a small office-studio at the Institute headquarters in the Radcliffe Yard, if she wants it. She can use it for storing storing junk, or she can virtually live there. No one expects her to be in. Often, several of the Scholars bring sandwiches and have lunch together at the Institute. They are get together, too, when each week a different Scholar gives a talk about what she's trying to do. About two-thirds of the Scholars usually show up at these 'colloquia," along with the Institute administrators, Mrs. Bunting, and whoever else is interested. (Cliffies are especially welcome, though few come, since the colloquia are not publicized.) But, there's no pressure on the Scholars to appear at lunchtime or at the colloquia. Their schedules are completely their own.

THE WEEK I visited one of those colloquia, Rachel Bas-Cohain, a young artist-Scholar in her late twenties, presented her experiments with reflected light, motion, and polarizing materials. As one of the guests, I wandered with about fifty women through her exhibit, a collection of whirring, flashing, rotating constructions made of glass, wood, water, and light. One construction consisted of two panes of glass pressed against each other and suspended from the ceiling. From one corner between the glass panes, water vapor seeped continuously upward in lacy bubbles. A light cast on the wall a shadow of the moving vapor lacework. The shadow looked like a spider web, growing, disappearing, and continually replacing itself.

The women around me stopped and watched, fascinated.

Later, in another room, Miss Bas Cohain began her presentation by reading a poem by Cummings. She then showed slides of paintings by Klee, Modigliani, Pollock, and various other modern artists, introducing them by saying simply that she liked them. The women in the audience sat silently in the dark, some smiling, some bewildered but receptive. Miss Bas-Cohain had said that she preferred not to explain what she was doing. She wanted to let the slides and the exhibit speak for themselves.

Few in the audience seemed to know exactly how to react (some women murmured confidentially to each other as if they were in a museum), but almost everyone looked pleased. There seemed to be something special about this almost completely female gathering. I got the feeling that all the women present were proud of Miss Bas-Cohain, perhaps because they identified with her as a woman. Among men, there's usually a competitive atmosphere, but that was absent here. Perhaps because they are still a minority group when it comes to having brilliant careers or even jobs, women feel something like the collective pride of the oppressed whenever one of them "beats the system" and stands out.

SINCE AN American woman's achievement is still scored mostly in terms of her husband's and children's happiness and success, she has much less at stake than a man when she attempts a career. She is considered exceptional if she just tries. So she can afford to be less critical of herself than a man can.

Today, as the demand for highly-educated employees increases, ambitious women seem to have an ideal situation: they are congratulated if they become wives and mothers and no more. If they have careers they get gold stars. It seems as if they can hardly lose.

But they can lose if they are ambitious, because many practical obstacles may prevent their careers. The society that considers marriage and motherhood sufficient goals for women can, and does, discriminate against them as students and careerists without feeling guilty. Although this country has one of the highest proportions of working women in the world, it falls far behind European countries in its postgraduate training of women, and in its acceptance of women in the professions. In graduate schools, men are notably preferred. Jobs that lead to promotion almost invariably fall to men.

Why? Supposedly, because women quit when they have babies. They are not considered good investments. Many are not good investments, but partly because society doesn't except them to be. It's as if the majority of woman made a deal with society: I won't feel guilty if you won't feel guilty. In other words, women will put up with discrimination (and not make society feel guilty) as long as society doesn't put pressure on them to try to achieve more (and doesn't make them feel guilty for not trying).