 Probability and Induction. Broad dealt with problems regarding induction—“the glory of science and the scandal of  philosophy”[16]  —in a number of papers. A sample of his work on the subject is the two early papers entitled “The Relation Induction and Probability” (1918, 1920). Broad’s focus is on the nature and justification of inductive inferences. He argues that unless the conclusions of such inferences are cast in terms of probability they all involve a formal fallacy. However in order to arrive at justified inductive conclusions we cannot simply place our confidence in any of the known principles of probability theory (such as those we employ in reasoning with regard to artificial situations with bags containing red and white balls, and the like): we need some further premise. Unfortunately, this premise is “extremely difficult to state […] so that it shall be at once plausible and non-tautologous” (1918, p. 389). Broad attempts to articulate the supreme principle needed. He argues at length that the principle needed says not simply (and crudely): “there is uniformity in nature.” It also says that the particular things or substances in the world subject to uniformity belong to a variety of natural kinds. Indeed, on closer reflection it is clear that “[t]he notions of permanent substances, genuine natural kinds, and universal causation are parts of a highly complex and closely interwoven whole and any of them breaks down hopelessly without the rest” (1920, p. 44). Notable also is the logic of conditions that Broad’s formulates in “The Principles of Demonstrative Induction” (1930b). He may quite well be the first who gave systematic attention to this  topic.[17]