 Finally, enumeration5 is an operation Descartes also calls “induction”, and consists in an inference from a series of particular cases satisfying a definite condition to all cases satisfying the same condition, as when one infers that “the area of a circle is greater than the area of any other geometrical figure whose perimeter is the same length as the circle’s” from the fact “this […] holds for some particular figures” (AT 10: 390, CSM 1: 27).