As its name implies this type of inductive research consists _in observing many instances which may exemplify the particular uniformity under consideration_. The process is quantitative rather than qualitative, the certitude of the generalization depending on the _mass of facts collected_ rather than on any striking resemblance or any detailed analysis. The aim is to observe, accurately if not scientifically, instance after instance until all doubt is removed. The outcome of such observation may be three fold. (1) The enumeration may be complete. This gives the so-called “perfect induction” which will receive attention later. (2) The enumeration may be incomplete and _without exceptions_; generalizing in this way from uncontradicted experience gives what are termed “_empirical_” truths. (3) The enumeration may be incomplete _with_ exceptions. It is obvious that this type of induction could give no valid generalization; but the result may be put in the form of a ratio between the uniformities and the exceptions. Such a procedure is a mere “_calculation of chances_” and the result simply an expressed probability. THE THREE KINDS OF SIMPLE ENUMERATION ILLUSTRATED. The subject to receive investigation is a _school examination_. (1) Complete enumeration. Every paper is read and marked; this leads to the generalization, “All the class have passed.” (2) Incomplete enumeration with no exceptions. Representative papers are read and marked in which no failures are found. Generalization, “Probably all of the class have passed.” (3) Incomplete enumeration with exceptions. Representative papers are read and marked in which there are 20 failures out of the hundred papers examined. Generalization, “Probably about 80% of the class have passed.” Briefly, simple enumeration may take the form of (1) _a perfect induction_, (2) _a probable induction_, (3) _a mere calculation of chances_. The first necessitates completed experience, the second uncontradicted experience and the third contradicted experience. =12. INDUCTION BY ANALOGY.= _Induction by analogy assumes that if two (or more) things resemble each other in certain respects, they belong to the same type, and, therefore, any fact known of the one may be affirmed of the other._ THE TYPE.