Introduction: Science and connoisseurship in the European Enlightenment.

A major theme of the European Enlightenment was the rationalization of value, the use of reason to determine the value of things, from diamonds to civilizations. This view of the Enlightenment is well-established in the human sciences. It is ripe for extension to the natural sciences, given the rich recent literature on affect, evaluation, and subjectivity in early modern science. Meanwhile, in art history, the new history of connoisseurship provides a model for the historical study of the evaluation of material things. Historians of natural history have already noted the connections between science, Enlightenment, and connoisseurship. The time has come to extend their insights to other areas of Enlightenment science. This means recognizing the breadth of connoisseurship - the social, linguistic, and disciplinary diversity of the practice - as understood in Europe in the eighteenth century and the latter part of the seventeenth century. An outline of the three papers in this special section gives an indication of how this historiographical project might be carried out.

The hand of the connoisseur: Gems and hardness in Enlightenment mineralogy.

Historians of natural history have shown that the study of plants, animals, and minerals was a form of connoisseurship in the eighteenth century. Historians of early modern experiments have linked scientific knowledge to the manual skills of artisans. I combine these two insights, arguing that connoisseurship in the sciences meant learning to touch, not just learning to look. The focus is on gems and mineralogy in eighteenth-century France. I show, firstly, that the study of gems was linked to the connoisseurship ("connoissance") of paintings. Next, books on gems were closely related to the new mineralogical treatises that emerged in the middle of the eighteenth century. These treatises formalized a distinction between "Oriental" and "Occidental" gems that was also a distinction between hard and soft gems. The best judges of hardness were gem cutters, a group that participated in mineralogy through the culture of collecting. Finally, the knowledge of cutters contributed to the quantification of hardness in the form of the hardness scale and the scratch sclerometer.

Iatrochemistry and the Evaluation of Mineral Waters in France, 1600-1750.

Existing literature on mineral springs in early modern France suggests that composition played a minor role in the evaluation of those springs. In fact it played a major role from at least the beginning of the seventeenth century. Composition was studied by a wide range of actors, from physicians in the provinces to chemists at the Paris Academy of Science, with a view to establishing the efficacy of particular springs against particular diseases. Iatrochemistry played a complex role in these evaluations. Followers of Paracelsus and van Helmont were among the first to perform chemical analyses on mineral waters. But there were physicians who studied composition without chemistry, or who used chemistry while opposing iatrochemistry. Conversely, there were iatrochemists who used chemistry to study mineral waters but not to evaluate them, and there were many chemists who gave at least as much weight to clinical experience as they did to composition.

The trials of theory: psychology and institutionalist economics, 1910-1931.

The rise of the institutionalist school of economics, in the 1910s and 1920s, has recently been given the historical attention it deserves. However, historical studies of the school have left two questions unanswered. First, to what extent was the institutionalist's interest in academic psychology (frequently declared in their meta-economic writings) realized in their economic writings? Second, what evidence of a fruitful collaboration with institutional economics can be found in the work of psychologists? In this paper I consider the meta-economic statements of three key institutionalists, Wesley C. Mitchell, John M. Clark, and Walton H. Hamilton, and two key economic works by Mitchell and Clark. I contend that these works show little systematic engagement of academic psychology. A study of psychological literature of the period yields the same conclusion; in particular, industrial psychology did not come into fruitful contact with institutional economics, despite the parallel interests of the two fields and their parallel rise after World War I.