effort to pave the way for speculative construction by means of exhaustive analysis. But with Hobbes and Spinoza the constructive element is predominant. The only way we can discover the facts and analyses by which these thinkers established their definitions and axioms is by a less direct method. In Leibnitz, the fourth and last of the group, the analytic method becomes more prominent again. He marks the transition to the eighteenth century, in which the problems of knowledge and of values acquire an exceptionally prominent place.
The increasing favor of the constructive method of this period is closely paralleled by the dogmatic character of these intellectual efforts. The principles of the mechanical theory of nature were regarded as absolute, objective truths. Leibniz likewise shows some divergence from his predecessors on this point, by the fact that he subjects even these “primary and real” attributes of things, which were regarded as absolute data in the mechanical theory of nature, to a critical analysis.
a. René Descartes (1596-1650) may be called the real founder of modern philosophy. He was the first to inquire after the ultimate presuppositions of knowledge, and his theory was the first to take explicit account of the mechanical explanation of nature in the statement of the problem. He applies the analytic method in searching for ultimate principles, but he quickly abandons it for the constructive method, because he believes it possible to demonstrate the necessity and rationality of the principles of the mechanical theory of nature. He regards the idea of God, the validity of which he demonstrates by the speculative method, as an absolute terminus of reflective thought. Descartes thus presents a peculiar combination of keen analysis and dogmatic assertion.