72. (2) Analogical Induction or Analogy. -- Scientific induction, with which we shall deal later on, disengages from among the many various accidents of a substance a natural property, and concludes with certainty that this property is the foundation of a general law.

Analogy is a reasoning of the same nature as induction, but its conclusion is only probable.

We employ analogical induction, or analogy, when, having recognized in two objects or phenomena certain characteristics which are really common, we infer that one or more other, heretofore unknown, characteristics of these objects or phenomena must likewise be the same.^{1}

{1} Analogy is abused in the sciences either by exaggerating resemblances to suit one's purpose, ignoring differences, or by taking a metaphor for a resemblance.