Ars experimentandi et conjectandi. Laws of Nature, Material Objects, and Contingent Circumstances

The scattered and pervasive variability of material objects, being a conspicuous part of the very experience of early-modern and modern science, challenges its purely theoretic character in many ways. Problems of this kind turn out in such different scientific contexts as Galilean physics, chemistry, and physiology. Practical answers are offered on the basis of different approaches, among which, in particular, two can be singled out. One is made out by what is often called an ‘art’ (thus not a science, rather an informed practice) of experiments. From the Renaissance until J. H. Lambert’s writings of the 1750–1760s, we can follow a train of reflections on the art of making experiments that deal precisely with the persistence of contingency in the material objects of pure science. The other is the analysis of contingency in probabilistic terms. They develop subsequently and eventually meet, as it can be seen precisely in Lambert’s work: among the first to pursue this path are Jakob Bernoulli and Leibniz.