In his Leçons sur les origines de la science grecque (1893), Gaston Milhaud, at that time a high-school teacher in Montpellier, lists the essential qualities of a good historian of science. These include extensive scientific competence to engage a Newton or a Fresnel, philological acumen to work on ancient documents, and philosophical sensitivity with which to grasp the nuances of scientific thought. In brief, a historian of science should be endowed with nothing short of universal knowledge. Milhaud, who eventually rose to the chair of history of science at the Sorbonne, had in mind Paul Tannery, but his depiction could easily describe John Heilbron, as Heilbron's latest book demonstrates. In approximately two hundred pages, Heilbron produces a formidable synthesis of the history of physics from Plato to yesterday (nearly literally). In so doing, he shows how physics changed dramatically not only as a result of the transformation of its problems, goals and methods, but also due to changes in the social status of its practitioners, its relations with politics and culture, and finally its budgetary impact.
Once upon a time in Greece, physics was physica, an eminently intellectual endeavour, tightly intertwined with ethics, blissfully indifferent to mathematics, and pursued by a handful of original freethinkers. Physica, a key concept of Heilbron's reconstruction of ancient science, is introduced in the first chapter, which, almost inevitably, takes the readers through the subtleties of Greek philosophy. In Greece, physica was invented. There, we meet its characteristically wide scope, embracing broad natural and cosmogonical themes in the attempt to explain everything under and above the sun. We also meet the tendency to frame explanations in terms of ultimate constituents of the world, the ineffable essence – or quintessence.
The second chapter is arguably the most stimulating of the entire volume. Contrary to many histories of physics, all too keen to jump to the Scientific Revolution, Heilbron pays due attention to Islamic science and notes that it did not merely keep ancient wisdom warm until the Westerners came along but rather actively selected, elaborated and enriched it. As has become increasingly clear in recent years, the Muslim world anticipated several themes of European science and culture. For one, practitioners of physica moved from private schools, such as the Academy or the Lyceum, to courts and administration offices. The study of the natural world ceased to be a purely intellectual pastime and began to bear important implications for faith and, consequently, politics. These interconnections deeply influenced the dynamics of physica. The degree of appropriation of Aristotelism, for example, depended on the leeway given by local leaders to the exegesis of sacred writings. More interestingly, the development of astronomy, especially in Baghdad, was greatly encouraged by religious as well as secular authorities. The vast number of observations made by Arabs would feed European astronomical research well into the eighteenth century.
Chapter 3 brings the narrative back to Europe. In the late Middle Ages and in the early Renaissance, knowledge was acquired from several sources and finally ‘domesticated’. The places of scientific and philosophical research changed again, with universities now taking the lead as cultural producers. Further, the source of wisdom shifted slowly from the Ancients to Nature. Scholastics combined faith and reason by cultivating the subtle art of argumentation. One of the main reactions to the Aristotelian system, nominalism, stimulated a descriptive approach to Nature and, with Buridan, Oresme and the Mertonian calculatores, produced some of the finest medieval physica. The strategic distinction between explaining the phenomena and merely describing them facilitated the Copernican revolution and, in general, the empiricism that lay at the foundations of the new science.
The transformation of physica into natural philosophy occupies Chapter 4. It is, in Heilbron's words, a ‘second creation’ or an ‘invention’ of physics (pp. 112–116). Prepared by numerous manifestos – Bacon's Novum Organum (1620), Galileo's Saggiatore (1623), and Descartes's Discours de la méthode (1637) – the Scientific Revolution emerged from universities and was taken up by the academies. More importantly, not only did it move increasingly away from theological themes – although theology remained a powerful factor – it also honed the questions while simultaneously extending them to scores of new and spectacular phenomena, especially those related to electricity and magnetism.
The last two chapters, dedicated to the nineteenth and twentieth centuries (with numerous forays in the twenty-first), could have benefited from a thematic rather than a chronological organization. At times, the reader runs the risk of being overwhelmed by the sequence of discoveries, events, places, scientists, disputes, experiments and theories parading before her. Nevertheless, Heilbron's compelling prose never goes awry, keeping the reader focused on the narrative core of the book. We then observe the emergence and development of new spaces of inquiry (cabinets become laboratories, which become research centres, which become even bigger laboratories) and new exotic entities (from fluids to ether, from fields to space–time and quarks). The cavalcade embraces all major scientific events of the twentieth century, including relativity, quantum mechanics and the development of space science in the Cold War, before eventually stopping at the Large Hadron Collider and the Higgs boson.
Heilbron's prowess with historical detail, his command of the technical aspects and his graceful style make this book an indispensable companion for the undergraduate in history of science, science and technology studies, and – why not? – physics. But even specialists in other sectors of history of science, as well as philosophers, may wish to avail themselves of this comprehensive synthesis that has been digested for us by a master of the discipline.
