Marilyn Ferguson, whose 1980 book "The Aquarian Conspiracy" became a bible
of the New Age movement, died on Oct. 19 at her home in Banning, Calif. She
was 70.

The cause was believed to be a heart attack, said her daughter Kristin
Ferguson Smith, of Los Angeles.

"A leaderless but powerful network is working to bring about radical change
in the United States," Ms. Ferguson wrote in her best-selling book. "Its
members have broken with certain key elements of Western thought and they
may have even broken continuity with history."

With a breathless sense of wonder and anticipation, Ms. Ferguson described
ideas and discoveries that promised a new age of personal fulfillment and
limitless potential. She surveyed pioneering work in mind-brain studies,
holography, psychotechnologies, parapsychology, holistic medicine and a host
of other emerging fields that, taken together, added up to "a benign
conspiracy for a new human agenda."

"The Aquarian Conspiracy," which she once called "a synthesis of essential,
life-giving truths," was the New Age movement's great catalog, gathering in
one volume many of the ideas, theorists and attitudes that would gain
cultural currency in coming years.

Some reviewers found Ms. Ferguson credulous, boosterish and highly selective
in her presentation of scientific evidence, but readers responded
enthusiastically to her tidings of the New Age. "It gave a name to
something, and that something was a cultural movement that had not been seen
from the broad perspective that she gave it," said Jeremy P. Tarcher, her
publisher. The moment was ripe. With books like "The Third Wave" by Alvin
Toffler and "Megatrends" by John Naisbitt appearing about the same time, and
the human-potential movement surging, Ms. Ferguson found herself propelled
into a new career as a lecturer, motivational speaker and teacher, although
her educational courses, she once said, were "more like shamanic journeys"
than ordinary seminars.

Marilyn Grasso was born in Grand Junction, Colo. After attending Mesa
College in Grand Junction and the University of Colorado, she began writing
poetry and short stories. In 1968, she published "Champagne Living on a Beer
Budget," written with her second husband, Michael Ferguson. An early
marriage ended in divorce, as did marriages to Mr. Ferguson and to Ray
Gottlieb.

In addition to her daughter Kristin, she is survived by her son, Eric, of
Beaumont, Calif.; her daughter Lynn Lewis, of Oakland; and six
grandchildren.

While studying transcendental meditation in Los Angeles, and watching her
children grow, Ms. Ferguson developed an interest in new findings on the
brain and consciousness that led her to write "The Brain Revolution: The
Frontiers of Mind Research" (1973). She also founded a journal devoted to
the subject, Brain/Mind Bulletin, which turned out to be so successful that
she created a companion publication, Leading Edge, in 1980. Described as "a
bulletin of social transformation," it dealt with politics, relationships,
business and the arts.

While editing Brain/Mind, Ms. Ferguson began organizing information that was
not suitable for it in folders. These supplied the raw material for "The
Aquarian Conspiracy." The book generated a belated sequel, "Aquarius Now"
(2005), which made little impact. Aquarian energies, perhaps, had flagged.
Or else the benign conspiracy had achieved the ultimate victory: its once
revolutionary ideas now seemed commonplace.

Ms. Ferguson's message was relentlessly positive. In the dawning new age,
people would exercise their talents to the fullest; war and social
hierarchies would disappear; and the human race, impelled forward by
thrilling new scientific discoveries, would embrace the happiness that
belonged to it by birthright. The future was not just bright, it was
radiant. She once told an interviewer, "We are going to see a burst of
creativity that will make the Renaissance pale in comparison."

Copyright 2008 The New York Times Company