Exploratory Experimentation: Goethe, Land, and Color Theory The style of investigation exemplified by Goethe’s experiments with color is often undervalued, but has repeatedly proved its worth. July 2002
https://physicstoday.scitation.org/doi/10.1063/1.1506750 quote <<Contrasting research strategies Newton’s and Goethe’s respective approaches to color illustrate two very different approaches to experimental research. We call them theory-oriented and exploratory experimentation. Theory-oriented experimentation is often regarded as the only relevant kind: It corresponds roughly to the “standard” view in the philosophy of science that experiments are designed with previously formulated theories in mind and serve primarily to test or demonstrate them. Such a view was stated forcefully by Karl Popper, who wrote, “The theoretician puts certain definite questions to the experimenter, and the latter, by his experiments, tries to elicit a decisive answer to these questions, and to no others. … Theory dominates the experimental work from its initial planning up to the finishing touches in the laboratory.” According to this view, it makes sense to perform an isolated experiment, and in particular an experimentum crucis, designed to judge between competing hypotheses. Newton largely followed such an approach in his experiments on color. By contrast, exploratory experimentation has been relatively neglected by historians and philosophers of science. Its defining characteristic is the systematic and extensive variation of experimental conditions to discover which of them influence or are necessary to the phenomena under study. The focus is less on the connection between isolated experiments and an overarching theory, and more on the links among related experiments. Exploratory experimentation aims to open up the full variety and complexity of a field, and simultaneously to develop new concepts and categories that allow a basic ordering of that multiplicity. Exploratory experimentation typically comes to the fore in situations in which no well-formed conceptual framework for the phenomena being investigated is yet available; instead, experiments and concepts co-develop, reinforcing or weakening each other in concert. Exploratory experimentation often results in the establishment of a hierarchy within a realm of phenomena. At the pinnacle are those phenomena—Goethe calls them primordial—that involve only the essential conditions and that are therefore attributed a special status. All other effects can be deduced or explained from those elementary ones by progressively complicating the experimental arrangement and adding new conditions. The connection between a particular effect and an elementary phenomenon is revealed by establishing a chain of intermediate effects. In his methodological essay The Experiment as Mediator Between Object and Subject, Goethe described the result of such an approach as a “series of experiments that border on one another closely and touch each other directly; and which indeed, if one knows them all exactly and surveys them, constitute as it were a single experiment….” He regarded this care to connect the “closest to the closest” as an experimental analog of mathematical deduction, which “on account of its deliberateness and purity reveals every leap into assertion.” In that context, isolated experiments are not very informative, let alone demonstrative, as they well might be in theory-oriented work. The difference is nicely illustrated by the exchange between Newton and an early critic, the Liège Jesuit Anthony Lucas, who brought forward many new experiments (including variations of Newton’s own), which he claimed could not be accounted for by Newton’s theory. Newton’s response was to insist that one “try only the experimentum crucis [Opticks, book 1, part 1, experiment 6],” for “where one will do, what need of many?” >>
