Stretching Science to the Breaking Point : THE MIND’S SKY: Human Intelligence in a Cosmic Context, <i> by Timothy Ferris,</i> Bantam Books, $22.50 340 pages

Timothy Ferris teaches at UC Berkeley and has written two best-selling books about science. With his reputation in mind but unfamiliar with his books, I eagerly read “The Mind’s Sky: Human Intelligence in a Cosmic Context.” I don’t know what his fans will think, but I’m disappointed.

“The Mind’s Sky” is about the nexus of neuroscience and astrophysics and carries a quasi-religious message. Ferris includes some nice distillations of current research in geology, planetary science and neurobiology, and there are a few memorable nuggets of information--like his explanation of laughter as the relief response when different parts of the brain get out of sync.

But when he tries to explain the meaning of it all, he enters the realm of science fiction. He seems haunted by the realization that in the long run, the very long run (several billion years), the sun will explode, carrying the planets and everything on them into oblivion.

Then, if no other civilization in space has chanced to pick up our radio and television signals, “All human science would have added up in the long run to nothing. . . . We would have added nothing to the totality of the perceived universe.”

Ferris defines the “perceived universe”--the only one that counts--as the intersection between what actually exists in space and what the human brain can process. Using the metaphor of a tree trunk with branching roots at one end and leafing branches at the other, or an hourglass, Ferris explains how the branches--the cosmos--are connected to the roots--the human brain--by the trunk, which carries signals from roots to branch and vice versa.

Divided into three parts, “The Mind’s Sky” is written in a monologue that is often irritatingly self-centered. There are, for example, references to Ferris’ son and the famous scientists with whom he has broken bread or spent an afternoon.

The first part focuses on SETI (the search for extraterrestrial life), a research project carried out with the help of radio telescopes. Ferris speculates on how extraterrestrials might establish listening posts, computerized stations or libraries or might even seed other species with DNA to carry on their destiny.

The middle section focuses on the human brain and the many regions that cooperate to form the conscious mind. And the last chapters attempt to bring together the mind and the cosmos.

At least Ferris does not doubt that there is, in fact, a real universe out there, although we can only perceive the part of it that our brains can fathom. It is likely, as we have learned from quantum mechanics, that what we perceive is affected by the very act of being perceived.

Ferris is understandably fascinated with recent research into the nature of perception. Hidden inside the brain are explanations for the most extraordinary universal phenomenon. One example he discusses is near-death experiences.

Sounding very mystical at first, Ferris eventually offers a physiological explanation for the feelings of well-being and the long tunnel with the light at the end that is so frequently observed by those who brush near death.

Why, he asks, should the experience of death release chemicals in the brain that make us feel good? What, he wants to know, is the evolutionary advantage of such feelings? Ferris utters a similar bewildered cry in the face of a sun that is destined to explode. Where is the purpose in a universe when the genius of an entire species can be destroyed in a second?

What he doesn’t want to accept, in organic evolution or on a galactic level, is the possibility that there is no reason: that everything, including intelligent life, may just be.

In his preface Ferris ingenuously advises the reader “to pick and choose among these chapters as he or she may prefer.” He even suggests that the last chapter may be skipped altogether. But ultimately, he doesn’t appear to mean this, for the final chapter is clearly his favorite.

In it Ferris proposes a philosophy of science which, he announces modestly, goes beyond physics, a field limited by old concepts of space, time, matter and energy. Resting on information theory, his “new scientific paradigm” suggests that the simple binomial system underlying computer logic may exist intergalactically.

“The Mind’s Sky” shows that Ferris is a true believer in something beyond the human race, some intelligence in space that will give our lives meaning. He seems to need extraterrestrials--the way others seem to need a god.

Next: Jonathan Kirsch reviews “In Quest of the Great White Gods” by Robert F. Marx (Crown) .