Human Options: An Autobiographical Notebook, by Norman Cousins. New York: W.W. Norton & Co. 224 pp. $9.95

Norman Cousins is concerned with the choices open to humankind at every level (personal, societal, moral, artistic, and so on) as we cope with challenges of the present and future.

He believes these options are limitless - that our capacities are unbounded, and ''no challenge is beyond human conception and reach.''

This central idea finds expression in countless related thoughts, culled mostly from pieces published during Cousins's many years as editor of the Saturday Review. The thoughts appear as individual paragraphs, grouped loosely together under headings such as ''Creative Options,'' ''The Cosmic Classroom,'' and ''Freedom as Teacher.''

Thus, although Cousins calls this volume ''an autobiographical notebook,'' the events of his life are touched upon only insofar as they elucidate ''one man's learning experiences during most of the twentieth century.''

In the course of them, Cousins had occasion to learn directly from the lips of the century's towering figures. He offers revealing - and often inspiring - -vignettes involving Helen Keller, Einstein, Hemingway, Churchill, and Nehru, to name only a few.

On almost every page an aphorism leaps out begging to be quoted: ''Speculation leads to learning, just as theory leads to science.'' ''What we have most to fear is not the triumph of communism but the default of democracy.'' ''A good writer - or any artist, for that matter - is a prism for refracting beauty and truth.''

By his own definition, Cousins is a very good writer indeed. His work shines with profound humanity and optimism, underpinned by a faith in goodness. So it is not surprising he also writes, ''What we believe is the most powerful option of all.''