MIND AND NATURE embodies the courage and drama of clear, honest thought by an oridinal and cultivated mind. Gregory Bateson, throughout his varied academic career, has remained an iconoclast - challenging and provocative, but always searching for synthesis and integration. Now perhaps this brilliant book can serve as a bridge between moral philosophy (in which psychology had its roots) and evolutionary biology.

Through his father, William, the eminent British geneticist, Bateson absorbed the intellectual excitement of the post-Darwinian debates. He studied biology at Cambridge, but switched to anthropology and headed off for extensive field work in New Guinea and Bali. There in 1936, he met and later married Margaret Mead, and they remained friends and collaborators even after their divorce in 1950.

In the '40s he was in at the beginning of the serious discussions of cybernetics, with Norbert Wiener, Warren McCulloch and John von Neumann. For many years he worked with alcoholics and schizophrenics as "ethnologist" at the VA Hospital in Palo Alto. He developed the famous "double-bind" theory of schizophrenia. Bateson is now considered one of the fathers of the family therapy movement and has had great influence on many social scientists, as well as the psychiatrist R. D. Laing. He joined John Lilly for experiments with communications with dolphins.

Always, he has been respected as a great teacher and his collected essays, Steps to An Ecology of Mind, has become something of a campus cult book. Last year Governor Jerry Brown appointed him to the Board of Regents of the University of California, hoping he would be a cage-rattler. Mind and Nature includes a critique of most university education, which he calls "obsolete" and a "rip-off." Now at 75, he writes with special urgency, as he's undergone major surgery "and was warned that time might be short."

His purpose in Mind and Nature is to examine "how we can know anyting. In the pronoun we, I of course included the starfish and the redwood forest, the segmenting egg, and the Senate of the United States." Bateson believes that ideas externalize themselves: wrong perception leads to wrong thought which leads to wrong action. The problem, he says, is the discrepancy between the way we think and the way the world really works. We think in linear terms - purpose-goal, cause-effect. But nature is made up of circular steady-state systems. We must learn, says Bateson, "to think as Nature thinks." To do this, he urges us to examine "how the world is joined together....; What pattern connects the crab to the lobster and the orchid to the primrose and all four of them to me? And me to you? And all the six of us to the amoeba in one direction and to the backward schizophrenic in another?"

His image is partly drawn from ecology, cybernetics and the social sciences: ecology demonstrates the connectedness of all life in cycles and chains of food and energy so that the system as a whole can respond to change, and yet tends to remain balanced and stable. Cybernetics describes the circuitry of computers and brains, and the role of negative and positive feedback in the processing of information and the control of actions, whether of machines or of humans. And anthropology examines cultures in an effort to understand how individuals react with each other and with groups, and how such reactions are shaped by perceptions and expectations on both sides. The common thread is context: an organism can survive only as organism-in-its-habitat; the computer controlling a machine is part of a circuit which requires the feedback of information, itself a part of the loop; and no human action occurs in cultural isolation - in every case there is a stimulus-response constantly reinforcing postively or negatively, establishing the founds of behavior.

Bateson's central idea is "evolution as a mental process." How can we account both for the profusion of species, the astonishing range of life forms filling almost every biological niche, and at the same time account for the persistence of species - stubbornly replicating themselves season after season, generation after generation, in monotonous uniformity? Bateson sees nature as both conservative and radical: fundamentally conservative in turning out through vast reaches of time cookie-cutter copies of identical cells with identical DNA. In his analogy to mental process, he calls this the rigor of cultural tradition. This integrity or inertia provides the keel and ballast which prevents wild gyrations in the natural world.

At the same time, the biological machine is not absolutely perfect, and tiny aberrations, a microscopic shift in the position of a chemical marker, an accident or turbulence, and the random element enters, brining mutation and change. It is the environmental context which selects which shall survive. Bateson believes cultural survivals follow this process just as surely as do biological species. In the case of culture, it is imagination - always challenging and questioning, upsetting traditions, flouting conventions, which provides the random. But the human environment also seeks to complete the circuit and return to a new steady state;. As in evolution, so with human thought: "rigor alone is paralytic death, but imagination alone is insanity."

Bateson sees dangerous parallels between Lamarckism - the theory that acquired characteristics can be inherited - and the predicament of modern man. Biologically, we can not inherit acquired change; but technologically, industrial societies confront us with changes which seem irreversible. As Carl Sagan has pointed out, we may be "the first species to take evolution into our own hands." Evolution and human thought both require self-correction, the preservation of genetic and societal options and the stability of the circuit. But if man falsely perceives himself as separate from and superior to his environmental context, he may imagine he can "manage" Nature. Bateson believes this prideful idea will not survive - and the idea itself is dangerous to man's future.