ABSTRACT
This chapter examines how Gottfried Wilhelm Leibniz, profoundly dissatisfied with the intuitionistic reaction against the ideal of formal reduction in his own century, undertook directly to argue against the positions elaborated by Rene Descartes and John Locke. Descartes stigmatizes reliance on formal demonstration or calculation as opening the door to sophistry and error, and argues that the establishment of conclusions by mere manipulation of a formal calculus, exclusive of intuition, is a “blind” process which precludes a real understanding of the truths arrived at. Descartes was very little concerned with the problem of necessary truth as such; what is rather emphasized throughout his writings is the problem of certainty or self-evidence. Like Descartes, Locke makes little effort to clarify the question of how people are to distinguish intuitable or self-evident truths from propositions which require demonstration, beyond the presentation of examples.
