Visions: How Science Will Revolutionize the 21st Century. - book reviews

Reason, Jan, 1998 by Kenneth Silber

Visions begins on a note of arrogance. Unlike previous efforts to chart the future of technology, Michio Kaku assures us, his predictions are likely to be correct. As science approaches a full understanding of the laws of nature, a scientific consensus is emerging about where technology is headed and on what timetable. This book, Kaku asserts, reflects that consensus.

Baloney. What is remarkable about many of the advanced technologies Kaku discusses - artificial intelligence, genetic engineering, nuclear fusion, electric cars - is the distinct lack of scientific unanimity about their potential. For every physicist who says that fusion is "the energy of the future," there's another who replies, "Yes - and it always will be." Even when the experts are in general agreement - as they once were about the infeasibility of cloning an adult sheep - consensus has hardly proven a guarantee of predictive accuracy.

Nonetheless, Kaku, a theoretical physicist and high-profile popularizer of science, has written an absorbing book, filled with thoughtful speculations about the 21st century and beyond. Visions sketches what might emerge from three 20th-century scientific upheavals: the "computer revolution," the "biomolecular revolution," and the "quantum revolution." These revolutions are interconnected, as Kaku notes; discovery of the DNA double helix, for example, relied on X-ray crystallography, a technique derived from quantum physics. Such linkages, he expects, will take on growing importance in the next century, in the form of DNA-based computers and other hybrid technologies.

Visions provides an intriguing (and explicit) rejoinder to The End of Science, the 1996 book in which journalist John Horgan argued that the era of scientific discovery is sputtering out in disappointment and confusion. Similar to Horgan (but unlike eminent scientists such as Roger Penrose and Freeman Dyson), Kaku believes that breakthrough insights into nature's workings, such as evolution and relativity, are now mainly things of the past. But where Horgan detected intellectual drift and technological stagnation, Kaku sees something very different: The age of discovery is giving way to the age of mastery. Having learned the universe's rules, humans are finally ready to become full-fledged players in the game.

The quantum, biomolecular, and computer revolutions, in other words, are enabling us to be "choreographers of matter, life, and intelligence," no longer mere passive observers of nature's dance. Yet even while taking this expansive view of technology's potential, Kaku is adept at recognizing technological hurdles and limits.

Computing power, Kaku expects, will become increasingly cheap and ubiquitous in the next two decades, manifested in such products as wearable computers, smart cars, and digital scrap paper. Helpful (but sometimes annoying) "intelligent agents" will sort your e-mail, update your schedule, and remind you to watch your diet. But before long, Kaku notes, chip making will bump up against the physical limits of silicon, and further progress will depend on the development of holographic memory, organic processors, quantum transistors, and other exotic technologies.

After 2020, Kaku predicts, the first glimmerings of true artificial intelligence will appear, as computers acquire common sense and as the Internet evolves into something similar to the "magic mirror" that imparts wisdom in fairy tales. After 2050, robots endowed with some degree of consciousness and self-awareness may roam the earth. Might humanity eventually be enslaved or slaughtered by its robotic creations? Kaku closes his discussion of artificial intelligence with an overview of the built-in safeguards that should be devised to prevent such an outcome.

Biotechnology also will make vast strides in the early 21st century, according to Kaku. By 2020, the genetic underpinnings of many hereditary diseases will be understood, and entire classes of cancer will be curable. People will own CD-ROMs containing their own personal DNA codes. Between 2020 and 2050, genetic research will see slower progress, as scientists grapple with the intricacies of gene function and protein folding. During this period, however, it will become possible to grow new vital organs in the lab, perhaps extending the human life span by decades.

After the century's midpoint, Kaku writes, "we may be able to manipulate life itself." Yet he is impenetrably vague about what this means. More interesting is Kaku's discussion of feats that probably lie beyond biotech's reach. Performing major design changes on human beings - say, growing wings on a person's back, in Kaku's whimsical example - is unlikely to be feasible even in the late 21st century. Consider the obstacles involved: The genes that initiate wing formation in a bird or insect may do nothing in a human (or may activate homologous organs, such as arms); these genes would have to be altered to allow a wingspan of some 20 feet; and the human's entire genome would have to be transformed to create the lighter bones and stronger muscles required for flight.