WE no sooner perceive things by the senses than we begin, consciously or unconsciously, to arrange and classify them in various categories according to the properties they appear to possess, to note causal relations, and to trace similarities between them. These three processes, with which we shall deal separately under the headings of Generalisation, Cause and Effect, and Analogy, are called Inductive Processes. Induction implies the collecting and arrangement of data and the formulation of generalisations, laws or rules to cover a number of data and possibly to account for them.