Abstract

A century and a half ago James Spedding wrote a two-volume review of Macaulay’s Essay on Bacon’. That review inaugurated a career dedicated to the study of Bacon, including a biography that is still, perhaps, the best extant, and the preparation of the collected works-by Ellis, Spedding, and Heath-which is still the standard edition in Bacon scholarship. Had I treated Kuhn’s new book with a similar degree of attention, the result would be a book-length study of Max Planck and his contribution to twentieth-century thought. Let others take up that task. Here is a mere outline of the task, a few hints. Such a story as Kuhn has attempted to tell is, of necessity, full of loose ends. The choice of which loose end to tie up may be ad hoc; the choice is then open to criticism. Or, it may be in accord with some principle; the choice and the principle are then both open to criticism. A detail may be wrongly presented or rightly presented but its role in the story wrongly judged. Nor is this all: the list of what may go wrong and be open to critical comments is already too long. A reviewer must, then, either cover all grounds by a book-length review, or make many questionable choices tacitly. Both options are unsatisfactory, and all that is left for the reviewer is to ask for his reader’s sympathy and indulgence and to attempt to be as transparent as possible. What is the book about? The title suggests the answer: it is the story of how the study of black-body radiation (see below) led to the idea that matter emits and absorbs radiation, i.e., light, not continuously, as required by the wave-theory of light, but in discrete bursts of energy, now known as photons. This idea was revolutionary. Thomas S. Kuhn, author of The Structure of Scientific Revolutions, has now written the story of one of the greatest and most exciting scientific revolutions of all time that of the quantization of light: the quantum revolution. One might expect this book, then, to be not merely about the quantum revolution but also about its structure. Is it? Most authorities on the matter tend to answer in the negative. This review takes the opposite stand and is thus a tribute to this book.