The Axiomatic-Deductive Ideal in Early Modern Thinking : A Cognitive History of Human Rationality
Euclid completed his geometrical proofs in the Elements (c. 300BC) with the abbreviation “QED” (quod erat demonstrandum). This phrase was not only used in mathematics in the early modern period, but also in deductive proofs in physics, astronomy, philosophy, and ethics. This chapter is a cognitive- historical interpretation of the axiomatic-deductive ideal that consists of some widely accepted pro