To go to bed, Tom Dempsey must first make sure that everything is in place - telephone, light switch, medications, wheelchair.

Then he removes the left arm of his chair and places it within easy reach. Next, he puts the slideboard between his seat and the bed. He slowly, slowly moves himself over by lifting his legs in a rope loop, suspended from an overbed frame.

When Dempsey finds a comfortable spot, he releases the loop. His decision is important, because he cannot easily change position during the night. Moving himself out of bed in the morning is even more arduous.

Dempsey, a writer in his early 30s, was just horsing around with his fraternity brothers at college a dozen years ago when, in a moment of vigorous camaraderie, he was jumped on and his neck was broken. He is now a quadriplegic, although a "strong quad," with strong arms.

Peter Trier, 26, needs assistance to move in and out of bed. Now a doctoral candidate in philosophy, he has been disabled since birth by hereditary muscular atrophy.

Trier's ritual of checking each item required for comfort and security at night is much the same as Dempsey's. He, too, sleeps alone - in a hospital bed covered with sheepskin which reduces bedsores - unless he has a lover on a foam mattress alongside his bed.

Despite the difficulties of even such a simple act as going to sleep, Dempsey, Trier and a growing number of disabled persons perfer independent living to staying with their families or to hospital or other institutional care.

The "crip lib" movement, as some call it, seems strongest in Berkeley, Calif., which is exceptionally hospitable to the disabled. The movement started in the '60s with a residence program for severely disabled students at the University of California. It has now grown into the Center for Independent Living and is the focus of a fascinating book, "Design for Independent Living - The Environment and Physically Disabled People," by architects Raymond Lifchez and Barbara Winslow (Whitney Library of Design, $25).

The aim of the Berkeley Center is "mainstreaming." That means more than providing disabled people opportunities similar to those of others, or helping them to liberate themselves from institutional warehouses or the emotional confinements of family care.

Like other liberation movements, the physical and psychological liberation of those who are often dismissed as "cripples" is essentially a new, broader, deeper application of the idea that all of us have a right to life, liberty and the pursuit of happiness. For "crip lib," the pursuit includes the liberty and happiness of personal independence: Needing help does not mean being helpless.

Members of the center live in communal arrangements, in pairs or alone in rented rooms or apartments which they adapt to their needs.

The center offers collective know-how about working the system - getting funds and disability insurance, coping with bureaucratic red tape, personal counseling, job development, transportation assistance, finding attendants, and opportunities for community and political involvement. Most important, the center provides various means of emergency assistance when needed. A minor breakdown of the electric wheelchair at night on a lonely street can be a major catastrophe.

Lifchez and Winslow are concerned with the physical aspects of disabled living that is not just a matter of ramps and curb cuts, electric door openers and voice-responsive telephones. It is a matter of sympathetic knowledge, of special physiological and psychological needs. Spinal cord injuries, for instance, frequently make the body unable to adjust to temperature change.

The disabled face dangers and live in psychological fear of dangers not shared by others. They are exceptionally vulnerable to muggers and purse snatchers and face the fears and hostilities of people who fear and/or hate the disabled. They are also more susceptible than the rest of us to infections and injury.

Lifchez and Winslow have drawn detailed profiles of seven disabled Berkeley students of different background, afflictions and ambitions and show us how they interact with their "intimate, dwelling and community environments," which means their beds and bathrooms, their apartments, and the world at large.

Although somewhat clouded by thick jargon and long, verbatim quotations of the sort of redundant, inarticulate stammering that seems to have become the American language, the book is absorbing and revealing.

It will be of invaluable help not only for designers who would help turn spaces into places for the disabled. It sets an example of how every architect and student of architecture should look at the people for whom he is designing.And it opens the eyes of anyone who wants open eyes to the changing values in our society. Lifchez and Winslow accomplish this with unsentimental empathy.

As Berkeley has shown, an entire community is capable of learning this. Berkeley not only has curb cuts and restaurant doors that can be entered in a wheelchair. It is beginning to view disabled neighbors as persons with career potentials that go beyond handicrafts. And it is beginning to view them as persons with sexual potentials. Some people in Berkeley, according to this book, reject the notion that only beautiful and athletic people have a right to love and be loved.

The changing attitude of the nondisabled affects their view of society and its values.

It challenges the notion that only perfect human specimens have a claim to be important and be granted dignity and justice.

This enters into the current discussions about giving the disabled equal access to public transportation, culture and education. It may indeed be cheaper to provide everyone in a wheelchair with a Cadillac, rather than adapting public buses and subways to his or her needs.

But that is not the point. The point is liberty. The point is that all humans crave the freedom to move about, to break their confinement, to explore and meander, to be part of the world. CAPTION: Picture 1, "The liberation of those often dismissed as 'cripples' is essentially a new application of the idea that all of us have a right to life, liberty and the pursuit of happiness."; Picture 2, no caption from the book, "Design for Independent Living"