Judson, whose history of molecular biology in The Eighth Day of Creation established him as a science writer of considerably elegance, here assays the nature of science itself. Through chapters called ""Pattern,"" ""Change,"" ""Chance,"" ""Feedback,"" and so on, he illuminates how scientists ""do"" science, rather than taking a historical or philosophical approach. On the whole this procedure works, though the reader may forget that all those abstract features simultaneously interact. In any case, Judson is free to range widely over luminaries in all fields from Galileo to Gell-Mann, from Harvey to Sir Francis Crick, to make a point. Like a good teacher, he often begins with a homely anecdote. Thus, ""Pattern"" begins with a description of the disruption in his own life pattern wrought by a trans-Atlantic flight. Frequently, too, the chapters are accompanied by brief interviews which underscore the point. A particular instance is that of English amateur astronomer George Alcock (apropos of ""Pattern""): through sheer naked-eye familiarity with the pattern of the night skies, Alcock was able to pick out the rare anomaly--in his case, no less than four comets and three novae. Judson is also concerned with scientific judgment and creativity, often repeating the dictum of Medawar and others on the dynamic interactions between theory and observation, and the necessity at times of discarding observation when it conflicts with good theory. Tales of scientific invention, often after a period of incubation--such as PoincarÃ‰'s boarding a bus and suddenly realizing that he had discovered a model for non-Euclidean geometry, or KekulÃ‰'s famous dream of the benzene ring--are familiar but useful examples. In contrast to the considerable biological depths of Eighth Day, no great demands on scientific knowledge are made in this book--which can serve very well as an introduction to science for high school students. The writing is always zestful, enthusiastic, and inviting, even to the inclusion of eight profound problems in science in search of solution.