Since science detached itself from philosophy at the beginning of the modern period and took on the form of a multiplicity of single sciences, the idea of unified science and of a universal scientific method has continued to attract leading thinkers. Leibniz, who realized the importance not only of a certain and fruitful method of inference but also of a suitable symbolization for the progress of science, presented a famous program for the construction of such a scientia universalis. Therein he sought "a characteristic of reason, in function of which the truths of reason — like those of arithmetic and algebra — could be attained through a calculation, to the extent that they are subject to inference".¹