 In science and in daily life we do not merely use unanalysed concepts. “We also assume uncritically a number of very fundamental propositions. In all our arguments we assume the truth of certain principles of reasoning. Again, we always assume that every change has a cause. And in induction we certainly assume something—it is hard to say what—about the fundamental ‘make-up’ of the existent world” (1924, p. 84).